Planning for Production of Freshwater Fish Fry in a Variable Climate in Northern Thailand by AQUADAPT

Planning for Production of Freshwater Fish Fry in a Variable Climate in Northern Thailand Anuwat Uppanunchai, Chusit Apirumanekul & Louis Lebel

Environmental Management ISSN 0364-152X Volume 56 Number 4 Environmental Management (2015) 56:859-873 DOI 10.1007/s00267-015-0547-4

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Author's personal copy Environmental Management (2015) 56:859–873 DOI 10.1007/s00267-015-0547-4

Planning for Production of Freshwater Fish Fry in a Variable Climate in Northern Thailand Anuwat Uppanunchai1,3 • Chusit Apirumanekul2 • Louis Lebel3

Received: 3 February 2015 / Accepted: 8 June 2015 / Published online: 24 June 2015 Ó Springer Science+Business Media New York 2015

Abstract Provision of adequate numbers of quality fish fry is often a key constraint on aquaculture development. The management of climate-related risks in hatchery and nursery management operations has not received much attention, but is likely to be a key element of successful adaptation to climate change in the aquaculture sector. This study explored the sensitivities and vulnerability of freshwater fish fry production in 15 government hatcheries across Northern Thailand to climate variability and evaluated the robustness of the proposed adaptation measures. This study found that hatcheries have to consider several factors when planning production, including: taking into account farmer demand; production capacity of the hatchery; availability of water resources; local climate and other area factors; and, individual species requirements. Nile tilapia is the most commonly cultured species of freshwater fish. Most fry production is done in the wet season, as cold spells and drought conditions disrupt hatchery production and reduce fish farm demand in the dry season. In the wet season, some hatcheries are impacted by floods. Using a set of scenarios to capture major uncertainties and variability in climate, this study suggests a couple of strategies that should help make hatchery operations more climate change resilient, in

& Louis Lebel llebel@loxinfo.co.th 1

Lamphun Inland Fisheries Research and Development Center, Department of Fisheries, Ministry of Agriculture and Cooperatives, Lamphun 51000, Thailand

Stockholm Environment Institute (SEI) – Asia Centre, Bangkok 10330, Thailand

Unit for Social and Environmental Research (USER) Faculty of Social Science, Chiang Mai University, Chiang Mai 50200, Thailand

particular: improving hatchery operations and management to deal better with risks under current climate variability; improving monitoring and information systems so that emerging climate-related risks are known sooner and understood better; and, research and development on alternative species, breeding programs, improving water management and other features of hatchery operations. Keywords Tilapia Flood Drought Aquaculture Hatchery Climate change Scenarios

Introduction Climate change, especially changes in the frequency or severity of droughts or floods, will likely have major effects on aquaculture (De Silva and Soto 2009; Pickering et al. 2011), and thus potentially also on global food security (Troell et al. 2014). Climate has a substantial influence on what species are cultured and where. Aquaculture systems and cultured organisms are typically sensitive to temperature, water availability, and quality, as well as impacted by extreme events. Most studies have focused on impacts on growth and mortality in outgrowth ponds and cages. The impacts of climate on hatchery operations and young fish have received less attention by comparison, though scholarship on this is potentially significant to aquaculture development, as maintaining supplies of quality fish fry can be a major challenge even under current climate variability (Das et al. 2013). Analysis of future climate scenarios in the northwest USA suggests that altered hydrological regimes would significantly influence water resources important to hatchery operations for Pacific salmon (Hanson and Ostrand 2011). These include both direct issues of meeting water

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requirements for hatchery operations, and indirect ones such as the need to adjust timings to fit altered flow conditions when fry are released back into rivers. Increases in air and water temperatures would also create management challenges for hatcheries. In response, Hanson and Ostrand (2011) suggest a number of information and monitoringrelated strategies, as well as the incorporation of climate change considerations, into hatchery management plans. A detailed model for one of the hatcheries suggested that, while salmon could tolerate the levels of projected climate changes for several decades, faster growth in summer when less water was available would lead to greater physiological stress (Hanson and Peterson 2014). Water cooling and changes to feeding regime were proposed as options to reduce the associated risks. Twenty years of time-series data on the prevalence of diseases in two hatcheries in Northern Finland—where water temperatures have significantly increased—showed that, overall, the incidence of infections increased with temperature (Karvonen et al. 2010). Different diseases, however, showed different patterns; with some increasing, others decreasing, and some showing no change with temperature. Over three decades, minimum water temperatures in the upper parts of the River Ganga, where aquaculture of the Indian Major Carps is widespread, have increased 0.5–1.4 °C (Das et al. 2013). Higher temperatures have adversely affected breeding patterns and reduced natural spawning of fish in the river, whereas hatcheries in the neighboring Gangetic Plains have been favorably impacted, with breeding seasons extended by 45–60 days (Vass et al. 2009). Severe droughts in 2009, however, had massive impacts on hatcheries, underlining their sensitivity to water supply which is also under pressure from other uses (Das et al. 2013). The ability of hatcheries to respond after disasters by quickly providing fish fry or larval shrimp can be important to livelihood recovery. This was clearly demonstrated in the extreme case in Aceh, Indonesia, following the 2004 Indian Ocean Tsunami (Mills et al. 2011). This and other studies also underline that the impacts of extreme events or climate changes on hatcheries and nurseries, may be distinct from those where fish are finally released and grow until harvested. Rainbow trout in Argentina, for example, are sensitive to high summer temperatures, which can cause problems with growth, fertilization rates, and mortality soon after hatching (Baez et al. 2011). For warmwater species like Nile tilapia, cool temperatures in winter can be a major constraint on fish fry production. In Egypt, hatcheries which use heated greenhouses and concrete tanks, are able to cope better with the colder periods of year, and these have demonstrated to be more profitable than those using earthen pond systems and greenhouse tunnels without heaters (Nasr-Allah et al. 2014).

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This study explored the sensitivities and vulnerability of freshwater fish fry production in 15 government hatcheries across Northern Thailand to climate variability. Thailand is one of the top ten fishery producers in the world. In 2013, the gross domestic product of the fisheries sector (GDP) was approximately 122 billion Baht at current market prices, representing about 1.0 % of GDP or approximately 8.5 % of GDP in the agricultural sector (NESDB 2014). In recent years, 40–50 % of the total yield of aquatic animal products has come from coastal and freshwater aquaculture (DOF 2012). The Department of Fisheries (DOF), under the Ministry of Agriculture and Cooperatives, has 65 units for production of freshwater organisms around the country: 58 Inland Fisheries Research and Development (IFRD) Centers, 1 Inland Aquaculture Research Institute, and 6 Aquatic Animal Genetics Research and Development Centers (DOF 2013). These stations have played a significant role in research and development of new techniques in addition to providing fish fry and extension services to fish farmers (Belton and Little 2008); ultimately, they also helped the development of private hatcheries (Belton 2012). Mono-sex tilapia capacities in hatcheries, for instance, emerged out of research initially done in 1989 at the Asian Institute of Technology in Thailand, and spread through personal relationships with alumni, ex-staff, and personal connections with key individuals within the DOF (Belton 2012). In Northern Thailand, Nile tilapia (Oreochromis niloticus) is the most commonly cultured fish. It is popular with farmers for its high growth rate and hardiness in a range of environmental conditions, as well as its tastiness to consumers. Most commercial farms use mono-sex strains because of their better growth rates. Recent work on the sensitivity of fish farms to climate change in Northern Thailand underlines the importance of access to sufficient clean water, in both earthen ponds on private farm land (Pimolrat et al. 2013; Sriyasak et al. 2013), and in suspended cages in rivers and reservoirs (Lebel et al. 2013). In some years, floods or high flows also have significant impacts, causing fish losses and deaths as well as inflicting damage to equipment (Sriyasak et al. 2014; Lebel et al. 2015b). These studies have also identified high prices and low-quality fish fry as important risks that fish farmers must manage, on top of water and climaterelated risks (Lebel et al. 2015a). We were unable, however, to find any published studies focused specifically on the impacts of climate variability or change on hatcheries in Thailand. The aim of this study was to get a better understanding of the potential implications of climate change on hatcheries—as a key part of the aquaculture sector—in order to support improved climate risk management in the shortterm, as well as longer-term strategic adaptation planning

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in the DOF. Three specific research questions are addressed: (1) how do seasonality, extreme events, and differences in climate among hatchery locations influence fish fry production; (2) how do individual hatcheries, and the DOF more broadly, respond to or take into account climate-related impacts on production in planning and operations; and (3) how could the production of freshwater fry for aquaculture in Northern Thailand be made less vulnerable to risks arising from climate variability and change.

Methods Study Area and Government Hatcheries This study was carried out in Northern Thailand (Fig. 1). The climate of the region is considered monsoonal. Figure 2 displays the average winter temperature and annual rainfall during 1981–2010 of this region. Notably, sites at higher elevation and further north are cooler (Fig. 2a).

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Variation in rainfall follows a more complex spatial pattern (Fig. 2b), and is highly seasonal (Fig. 3a). There are 15 IFRD Centers in Northern Thailand (Fig. 1). One of the functions of the IFRD Centers is to act as hatcheries. Fish fry are produced for sale to private individuals, as well as grown for release into public water bodies to increase their productivity, to meet conservation objectives, and for ceremonies on key national holidays, such as the King’s birthday. Some fish may also be given to farmers impacted by floods, droughts, or disease outbreaks. In the Lamphun Center for the 2013 financial year, for example, 24 % of total fry produced were sold, and 76 % were released into public water bodies. Most stocking of public water bodies is done in response to requests from local community leaders or officials. Only native species are released into rivers and open water bodies; tilapia and other species favored by recreational fishers may be stocked into closed water bodies. Exact statistics are difficult to obtain for private sector hatcheries, and thus it remains unclear what fraction of fish fry

Fig. 1 Location of the Inland Fisheries and Development Centers (hatcheries) in Northern Thailand. Four main rivers in the upper Chao Phraya basin are also shown

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Fig. 2 Gridded average DJF temperature (a) and average annual rainfall (b) over the period of 1981–2010 in the four main river sub-basins in Northern Thailand

supplied to farmers in the region comes from these government Centers. Interviews Officials from all 15 IFRD Centers (Fig. 1) which produce fish fry for sale to farmers in Northern Thailand were interviewed. In most cases, the Director of the Center responded to the survey questions; in one case, it was a senior fishery biologist who was responsible for fish fry production. In addition, five fisheries experts with knowledge about hatchery operations were also interviewed. Interviews were conducted between 4 March 2014 and 21 April 2014. Interviews were carried out using an interview guide. Questions covered background information on: the responsibilities and experience of the individuals interviewed; characteristics of the location; and facilities of the Center. More detailed sections were about: planning and production of freshwater fish fry; the impacts of past flood and drought events; the impacts of other extreme climate conditions; responses to extreme events; and, suggestions on ways to strengthen the management of climate-related risks under current variability, as well as, adaptation to future climate changes. All interviews were taped, transcribed, and coded in NVIVO qualitative software. The higher levels of the coding tree covered the main question areas described above. Lower levels were based on themes that emerged during the analysis. To get a farmers’ perspective on fish fry quality, we analyzed results from recent surveys carried out on a

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related project. Fish farmers who rear tilapia in river-based cages (n = 662) and earthen ponds (n = 585) were asked about their levels of concerns about various sources or risks to the profitability of their farms, and how they managed those risks on a 5-point Likert scale. Details of these surveys of fish farmers can be found elsewhere (Pimolrat et al. 2013; Lebel et al. 2015b). In this paper, we focused only on evidence related to the quality of fish fry. Climate Change Scenarios Climate data used in this study were from the Integrated study on Hydro-Meteorological Prediction and Adaptation to Climate Change in Thailand: Forcing data (Kotsuke et al. 2014) and driving Data (Watanabe et al. 2014) were used for present (1981–2010) and near-future (2040–2059) analysis, respectively. The future atmospheric forcing dataset was created by correcting the bias in nine Atmosphere–Ocean coupled General Circulation Models, run under Representative Concentration Pathways (RCP) 4.5 and RCP 8.5. Apart from differences among models, multi-year variability in projected precipitation is high (Lacombe et al. 2012), as is historical inter-annual variability (Fig. 3a), strongly suggesting that consideration of alternative scenarios, as a way to acknowledge uncertainties, is warranted in planning and evaluating adaptation options. To this end, four qualitative climate change scenarios were constructed to capture key features of recent projections for future climate and water flows in Northern Thailand, and their

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and February, implying stronger seasonality of rainfall and flow, consistent with the more seasonal scenario. Other recent studies using different models and emission scenarios, while also projecting wetter conditions, suggest a longer duration of wet in the Upper Ping part of the basin, which follows the less seasonal scenario (Sharma and Babel 2013). In this latter study, the average precipitation for the set of downscaled projections from different models under the higher emission scenario (RCP 8.5) for the Ping basin, for example, was most consistent with the wetter scenario (Fig. 3c). It is worth noting that projections further into the future (2080–2099) suggest even wetter conditions. The potential impacts of changes in temperature on fecundity were explored using an empirically derived equation for fecundity (eggs/spawn) versus water temperature (TW in °C) adjusted for body size (W in grams) based on 170 estimates from 28 papers reviewed with relevant information: fecundity = -14. 8 T2W ? 772 TW ? 3.04 W - 9747 (R2adj = 0.72, P \ 0.001). This equation implies a maximum fecundity at 26.1 °C. A relationship for hatching rate (%) versus water temperature was derived based on 167 estimates from 21 sources: hatching rate = -0.519 T2W ? 28.7 TW - 333 (R2adj = 0.16, P \ 0.001). This equation implies a maximum hatching rate at 27.7 °C. A relationship for fry survival rate (%) to maximum of 30 day versus water temperature was derived based on 163 estimates from 25 sources: survival rate = -0.161 T2W ? 8.65 TW - 32.4 (R2adj = 0.08, P \ 0.001). Including days (7–30) in model did not significantly improve fit. This equation implies a maximum survival rate at 26.8 °C. A fourth regression, based on unpublished pond measurements in Northern Thailand, was used to estimate water temperatures based on air temperatures (TA): water temperature = 6.577 T0.438 (R2adj = 0.52, P \ 0.001). A

Fig. 3 Average monthly rainfall: a For the Ping Basin in the period 1991–2010 also showing climate variability; b Stylized schematic of rainfall distribution in the four scenarios used in this study compared to the historical baseline; and c for the Ping Basin in the periods 2040–2059 and 2080–2099 compared to historical pattern from downscaled projection under the RCP 8.5 emission scenario

significant uncertainties: wetter, drier, more seasonal, and less seasonal scenarios (Fig. 3b). Kotsuke et al. (2014) showed six models that projected large increases in runoff for the Chao Phraya River Basin, with the wetter scenario the most likely. Champathong et al. (2013) analysis suggested that rainfall would increase between April and August, with peak discharge downstream in September, but also reduced discharge in January

Results Geographic Patterns in Fry Production Nile tilapia fry—especially mono-sex tilapia (Table 1), which have been treated with hormones—remain the product most in demand by farmers, as they are easy to rear, grow well, and the domestic consumer market demand has been high. Row entries in Table 1 have been sorted from north (at top) to south (at bottom). The total proportion of Nile tilapia production increases when moving South (Spearman rank correlation = 0.60, P \ 0.05). Other aquatic organisms sought and produced, include: hybrid catfish, silver barb, climbing perch, striped catfish, channel catfish, common carp, and common lowland frog.

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Table 1 Fish fry production sold by IFRD Centers in Northern Thailand for the 2013 financial year (October 2012–September 2013) IFRD center

Fish fry production (hundreds of thousands) Normal Nile tilapia

Mono-sex red Nile tilapia

Mono-sex Nile tilapia

Other fish fry

Total fish fry

Chiang Rai

3.7

8.7

24.0

88.0

124.3

Mae Hong Son

1.2

–

11.2

12.4

Phayao

5.2

–

5.2

10.4

Nan

7.3

–

15.2

22.5

Chiang Mai

2.0

6.3

1.1

4.3

13.6

Lamphun

12.2

2.4

3.9

6.8

25.3

Lampang Phrae

9.3 5.5

0.1 5.1

11.4 4.1

12.2 33.2

33.0 47.9

Sukhothai

12.4

20.8

7.4

13.5

54.1

5.5

17.8

–

68.1

91.4

Phitsanulok

11.8

28.3

5.4

47.5

Phichit

15.1

9.4

–

20.8

45.4

9.5

46.2

10.1

17.8

83.6 55.9

Tak

Kamphaengphet

1.9

Phetchabun

25.4

8.9

1.8

19.8

Nakhonsawan

10.9

10.7

4.8

4.6

30.9

137.0

164.8

70.6

326.0

698.4

Total

Source: compiled by authors from individual center statistics

Occasionally, other species have been tried but they have not lasted long. ‘‘Under normal temperature conditions, Nile tilapia fry are in high demand. This is because Nile tilapia is easy to culture, fast-growing and tolerant to disease. They rarely have problems with hardiness.’’ The relatively high proportion of non-tilapia fish fry in some centers (e.g., Chiang Rai, Prae) was primarily because supply of tilapia had been exhausted and farmers had no choice but to take up other species. A few centers also produce large numbers of giant freshwater shrimp, postlarvae (e.g., Tak), but this production is not included in Table 1. Prices from the centers, it should be noted, are usually less than half that from private hatcheries. A key rationale for fry production, according to national policy, is to ensure availability of low-cost fish fry for small-scale producers. Hatchery officials also believe that, in general, ‘‘farmers have more confidence in fish fry from DOF than from private farms, which perhaps, some farms are good, but some farms are not. Ours may be good and farmers trust us, so they purchase fish fry from us all the time.’’ Discussions with commercial farmers suggest that they do not always share the same views about which sources provide fry of the highest quality. Overall, almost 80 % of fish cage farmers and 68 % of pond farmers surveyed were concerned or very concerned about the risks to profits of low-quality tilapia fish fry. Overall, 84 % of cage farms had problems with disease in the

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past 2 years. Of these, 75 % attributed, at least in part, those problems to low-quality fish fry. Only 16 % of pond farmers had recent disease problems, but of these, 60 % considered low-quality fish fry a contributing reason. Fish cage and pond farmers who were more concerned about risks to profits risks from low quality of fish fry, also expressed greater concern about cold spells, heavy rainfall, floods, and droughts (Spearman rank correlations, all P \ 0.01). There was an association with heat waves in case of pond but not cage farms. Fish cage farmers who had suffered significant impacts from floods or droughts in the last 2 years, however, were not more concerned about risks of low quality fish fry. This suggests that perceptions of risk were not dominated by recent experience of climate-related impacts. Fish cage farmers who perceived that flood water quality (debris, sediments, rubbish) had worsened since they first began fish farming, were significantly more concerned about the risks to profits due to low-quality fish fry. The main steps in production of Nile tilapia fry are typically as follows. First, male and female broodstock are introduced into a concrete tank at a ratio of 1:2 for breeding. After 7 days, all female fish in the tank are checked for eggs—Nile tilapia are mouth-brooders and sexes distinct—which are then harvested if found. Females are typically re-checked once per week. Harvested eggs are kept in well-aerated containers with high circulation for 3–7 days until they hatch, and yolk-sacs are depleted. The fry, now able to feed, are moved to fine mesh cages where

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they are fed feeds containing sex hormones for 21 days, so that they will develop into males. Typically, 97 % of so treated fry develop as males. The fry are then nursed with normal pellet feed in cages for 7–10 more days before they are sold. Some fry are not treated with hormone-leaden feed; they are left to grow to maturity over 4–6 months, and then used for breeding purposes in the next cycle. In most cycles, the best 30 % of each stock is kept. If fish production declination is detected, broodstock is changed. Improved genetic strains of tilapia come from the Aquatic Animal Genetic Research and Development Institute; for the Northern region, this is located in Uttaradit (Fig. 1). Planning Production Fishery hatcheries ‘‘have to follow general government rules and regulations,’’ but individual stations are given some authority to draft and adjust their annual production plans by the DOF central administration. This is important, as it provides the flexibility needed for individual centers to respond to changing farmer demands in their service areas. Annual plans cover separate budgets for production for release into public water bodies and for sale to farmers, and usually do not change much from the previous year’s target. Proposed plans are adjusted and approved by the central administration, taking into account the total budget allocation they have received. If flooding or other severe disruption occurs to a hatchery’s operations, part of a year’s budget may be re-allocated to other centers to make up for production shortfalls, but otherwise, there is typically no within-year adjustment of production plans or budgets. Under normal circumstances, actual production is usually within 5–10 % of targets in the annual plan. There are a few constraints with current regulations. For example, fish fry cannot be sold on weekends or during public holidays. While most prices are set centrally and standardized, some size-species combinations are not covered, and thus left for the individual centers to decide; this is to say, fish fry prices are not adjusted seasonally. Regulations and procedures on introducing new temperate species for culture are complex and can take a long time to complete inhibiting experimentation and innovation: ‘‘We had some temperate fish to culture, but got stuck with rules and regulations and we did not have enough agility or time to push our plan through.’’ Annual production plans specify quantities of each type of aquatic animal in each month. The IFRD Centers have to consider several factors when planning production. First, is to take into account farmer demand, including species and seasonal timing. This requires analysis to ‘‘identify trends in sale of fish fry by considering records from last year as well as purchase orders.’’ Plans are adjusted mainly to meet customer demands by species and quantity of fish fry each

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month, which can vary by location. Seasonality of climate conditions and extremes influences demand for fish fry: ‘‘In the dry season, farmers will rarely purchase fish fry as there is not enough water to culture fish. During the winter, farmers will purchase less perhaps because of the slow growth rate. In the period of heavy rain, farmers will not purchase either as they are afraid of flood.’’ Overall, production of fish fry varies strongly with the seasons, being much higher in the warmer and wetter months of the year, but beginning to fall by September in anticipation of the onset of drier conditions to come (Fig. 4). Second, is to consider production capacity of hatchery for freshwater fish fry. For example, there must be an adequate supply of good quality broodstock and system performance in terms of ‘‘survival rate, growth rate, health and size should conform to DOF standards.’’ This in turn depends on the quality of facilities in terms of aerator and water systems, and having sufficient breeding and nursing ponds ready for use. Water resources for production systems have to be of good quality and in sufficient volumes year-round for production of fish fry, in both hatchery and nursery sub-systems. Third, preparedness of a Center for production of individual species of fish fry also has to be taken into consideration, due to the differences in breeding and maturation seasons. Planning must take into account reproductive cycles, for instance, when a species spawns,

Fig. 4 Monthly proportion of total annual fish fry production sold for 2013 financial year for all Inland Fisheries Research and Development Centers in the Northern region of Thailand (October 2012– September 2013)

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in order to produce sufficient fry to meet demands throughout the year. ‘‘In order to make a plan, it is necessary to study the biology of each type of aquatic animal, climate information, rainfall and importantly, historical data and background information on broodstock and culturing.’’ Experience from previous years about the months suitable to culture fish is important to adjusting plans by seasons. Nile tilapia, for instance, are produced throughout the year, but production levels are reduced in the cooler, drier seasons, especially in Northern Centers. Finally, production plans must fit within allocated budgets. Financial calculations for hatcheries were explained by one official: ‘‘We firstly take a look at the expected income per expenses. Then we make a plan, for instance, if we need to show at least a million baht income, how many and what kind of fish we need to produce.’’ Central government budgets are allocated according to the Center’s plans. To respond to the increasing demand by farmers for fish fry, especially of Nile tilapia, Centers have introduced several strategies. First, is to focus on broodstock management; numbers of broodstock are increased and selected for strong fish fry, in order to avoid inbreeding and achieve higher growth rates. Second, is to continue developing fish strains to obtain good quality fish fry, for instance, with resistance to diseases: ‘‘We found that in the past 3 years, fish fry are scarce and the quality of fish fry are poor and low resistant to disease, so the total output is inadequate relative to the market demand.’’ Improving genetic stocks so fish are fast-growing, resistant to disease, and are able to spawn throughout the year are important objectives. Third, is to expand and improve efficiency of hatchery and nursery operations to increase production. One way is to increase the number of cement ponds, and another is to move toward closed, recirculating systems, with water treatment and filtration technologies. As available space and resources to increase ponds on existing hatchery centers is often limited, however, another strategy proposed was to train and promote more farmers to take on breeding and nursery functions themselves, i.e., produce ready-tosell fish fry using DOF strains. Finally, as climate and water conditions at any given time vary in Northern Thailand, it is possible to transport both fish fry and broodstock to where they are needed most from where they are easier to produce. Dry Season and Water Scarcity In the dry season, demand varies more closely with water availability for fish ponds and levels in rivers for cage culture. As one hatchery operator in Sukhothai explained, ‘‘This dry season a large number of fish fry can be produced, but farmer demand is low because there is not much

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water for fish culture.’’ In making decisions to stock, farmers are responding to their expectations on water supply, and this impacts their demand for fry. In an extremely dry year, farmers’ demand for fish fry will be greatly reduced therefore. In some centers with less access to water, such as in Lamphun—where the station is situated at a high elevation relative to its surrounding land, and there is no direct access to natural water bodies—rainwater harvesting, water storage, and dry season management are critical. Some centers on the other hand, are located in mountainous regions, and utilize only rain water for production of fish fry, and thus often lack water in the dry season to continue the activity productively. By the same token, some are located far from natural water sources, and so they have to use water pumps which contribute to higher expenses. Moreover, water transfers increase the risks of introducing diseases or other water quality problems into a hatchery. Groundwater may provide another option in some locations, but costs of running pumps remain an issue. On the other hand, culturing tilapia broodstock in cement ponds can reduce water usage compared to earthen ponds, and so is a point worth taking action on. In some centers, like Lamphun, production systems have been modified so that it becomes a recirculating system; though other Centers have considered this option, they worry about water quality issues: ‘‘recirculating system for water reuse should be considered, but the quality of reused water may be lower. We should also be careful of disease.’’ The used water from hatchery and nursery is like wastewater; it is full of organic matter, high in hydrogen sulfide, high in ammonia concentrations, low dissolved oxygen content, contains a lot of pathogens, and therefore must be treated with chemicals and filtered before reuse. In years with lower than normal rainfall, breeding and nursery operations can be affected significantly as a consequence of competition with other water users during shortages. One official from Nakhonsawan commented that ‘‘because of a large number of rice farmers in the surrounding area of the center they were at risk. Farmers take all the water, so we are not able to pump water to use for fish fry production. Instead, we have to use water from the storage pond for fry production and water quality is lower.’’ Wastewater released from human settlements, agriculture, and industry can exacerbate water quality problems for fish fry production. As urbanization proceeds, hatchery operations may be increasingly at risk. Hatcheries can deal with water quality problems by exercising frequent monitoring and storing water in ponds prior to use. Pre-treatment can be accomplished through aquatic plants and micro-organisms: ‘‘Our storage ponds are abundant, so we use electric water pumps to collect water in the storage

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ponds. Instead of directly pumping swamp water into broodstock ponds, we use water treated in storage ponds.’’ Wet Season and Flooding Hatchery centers, such as the one in Nan which is located in a lowland valley area, are vulnerable to flooding. Floods can damage equipment, breeding, and electrical systems. Broodstock and fish fry may escape as a result. Typically, production must cease for 3–4 months, and it may take up to a year to resume full, normal operations. In one location, this was solved by building a dyke around the Center. In another Center, it was acknowledged that little could be done to protect the Center from major floods: ‘‘If there is a flood, it is difficult to protect as there is too much water. Suppose it flooded like the year 1995, we cannot save anything in time.’’ In more moderate floods, netting of ponds can help reduce losses and unwanted fish intruders to ponds during floods. Extreme events can have big impacts on hatcheries, so they should be planned for from the start: ‘‘a basic survey in the areas should be carried out to consider risks of water shortage and flood history, to guide preparation of a protection plan in advance.’’ Dykes around facilities in vulnerable locations need to be inspected and repaired if necessary. Pumps and storage ponds should be ready to drain and divert flood waters. Center managers argued that impacts of floods on well-managed and well-prepared systems will be relatively low. Another important wet season challenge is high levels of cloud cover. Persistent, thick cloud cover can suppress normal day-time oxygen production by phytoplankton in broodstock and nursing ponds, resulting in low DO levels that cause stress, in turn effecting the health of fish. This problem is also an important management issue in later stages in earthen ponds as well (Sriyasak et al. 2013). Timely, supplementary aeration can help deal with this problem, but equipment needs to be in working condition and ready to deploy at a notice. Extreme Temperatures Extreme temperatures effect production of fish fry. Cold weather results in fewer eggs being produced and higher mortality rates after hatching. In addition, broodstock fish eat less and grow more slowly. Production in cold periods drops by as much as 60–70 %. Tilapia fish prefer warm conditions: ‘‘of course in winter our production rate will be less because temperature plays a major role in production system, decreasing the total output. Normally, the proper temperature for aquatic animals is approximately 25–32 degree Celsius, but extreme cold weather last year, which was lower than 10 degree Celsius, caused many problems.’’

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Some hatcheries cease production in such events, while others employ electric heaters for short-term cold spells; in particular, in hatching operations. For other stages however, the water bodies are too large to be manipulated in this way. Extreme high temperatures or heat waves reduce tilapia spawning and also have an impact on fry mortality, ‘‘because high temperatures cause too rapid development of fish fry, leading to malformations and death.’’ On the other hand, warmer average night-time temperatures might shorten hatching periods, leading to less healthy fish fry. Phytoplankton blooms can also cause problems with water quality and dissolved oxygen levels. Very hot weather conditions prior to the start of wet season stimulates phytoplankton blooms in hatchery ponds. Ammonia concentrations can also get high. Parasite infestations also appear to be more prominent during weather transition periods. To prepare for heat waves, feeding should be reduced; for example, by skipping an afternoon feed, as fish eat less at this hour and to boot, this reduces food waste and levels of organic nutrients in ponds. If there is sufficient water, managers may also consider changing water in concrete ponds. Adjustable roofs to shade ponds can be used to avoid risks of excessive high temperatures in cement ponds; during colder weather, roof sections are opened to maximize sunlight. Using solar energy, it is already possible to gain some control over water temperatures, especially in more closed systems. However, ‘‘for nursing fish fry in earthen ponds, it is hard to control external temperature,’’ and production falls under extreme temperatures. Potential Impacts of Warmer Temperatures and Changes in Rainfall Four scenarios were developed to capture, as a set, the main uncertainties about future climate likely to have important impacts on hatchery operations (Fig. 3b). Across scenarios, rainfall patterns in different seasons, relative to baselines, are distinct, and thus likelihoods of floods and droughts also differ (Table 2). In all scenarios, average temperatures increase substantially. In the benign, less seasonal scenario, extreme heat waves do not become more frequent, whereas in the other three scenarios they do (Table 2). The potential impacts of higher temperatures on key hatchery variables were studied in more detail using empirical models. The expected increases in temperature will result in large declines in fecundity in the three representative sites in the warmest month (April), especially in Pichit in the south, where average temperatures are already high (Fig. 5a). In the coolest month (December or January) at each site, the projected changes under both emission

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Author's personal copy 868 Table 2 Potential impacts of climate on hatchery operations under four climate change scenarios for 2040–2059 in Northern Thailand

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Changes and impacts

Wetter

Drier

More seasonal

Less seasonal

Average

Heat waves

Cold spells

Climate changes Temperature

Rainfall Annual

Wet season

Dry season

Flood

Drought

Facilities

Water quality Disease prevention

? s

Extreme events

Potential impacts

Fecundity

Hatching rate

Fry survival

Fry production

Spatial and seasonal differences are considered in the text For climate change, a positive (?) sign indicates increase and negative (-) a decrease, while a circle (s) indicates no change relative to recent climate For impacts, a positive (?) sign indicates more favorable, negative (-) more adverse, and a circle (s) no difference

scenarios would have a positive effect on fecundity in two Northern sites (Chiang Mai and Nan), but would have small negative effects in Pichit. The patterns for hatching rate are similar, but smaller and less negative (Fig. 5b). In the coolest months warmer temperatures would have positive effects on hatching rates in all sites. In the warmer months, effects are all negative and largest in Pichit—the warmest site. The projected changes for early fry survival are smaller than for fecundity or hatching rate, but follow a similar pattern (Fig. 5c). For all three key hatchery variables, the impacts (positive or negative) tend to be more pronounced in the longer-term (2080–2099) and with higher emission assumptions (RCP 8.5, Fig. 5). Based on current understanding of climate sensitivities of hatcheries, the potential impacts relative to a current climate baseline in the wet and dry seasons were qualitatively assessed to include other factors in addition to temperature (Table 2). In the wetter scenario, for instance, the increased likelihoods of floods in the wet season and even hotter temperatures meant impacts on fish fry production were negative. In the cool, dry season, however, the warmer conditions and increased supply of water were likely to be more beneficial in the upper North (e.g.,

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Chiang Mai) than in the lower North (e.g., Pichit, Fig. 5). In the drier scenario, lack of water meant that there was no opportunity to benefit from the warmer temperatures in the cool season, so net effects were also likely to be negative as a result of lower water quality and increased disease risks. In the less seasonal scenario, although there was no net increase in rainfall, the likelihood of droughts is reduced, so some benefits were expected (Table 2). Higher risks of floods in the wetter and more seasonal scenarios would have negative impacts on hatchery facilities. The more seasonal scenario would have the most adverse impacts as there would be increased risks of floods, droughts, and extreme temperature conditions. Implications for Adaptation Hatchery operators believe that a changing climate with more extremes could increase stress on fish fry, making them weak and susceptible to diseases: ‘‘Global climate change influences seasonal change, rainfall and increasing or decreasing of air temperature, which directly and indirectly affects production of fish fry. Those impacts include increased uncertainty of achieving production as planned, and unhealthy fish fry.’’ Interviews with hatchery officials

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Fig. 5 Projected changes in absolute fecundity (a) and hatching rate (b) of female nile tilapia, and early survival of their fry (c) at three sites in Northern Thailand under the RCP 4.5 and 8.5 greenhouse gas emission scenarios for warmest and coolest months. Change estimates

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are based on comparison of expected fecundity, hatching and survival rates at temperatures in 2040–2059 or 2080–2099 relative to those in the baseline period of 1980–2004

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provided some insights into their perspectives on how to improve policies, plans, and practices in response to challenges from current climate variability, and adapting to future climate change. To address climate change effects on broodstock, for instance, hatchery managers argued that it will be important to manipulate or control environmental conditions in ponds, for instance, through water exchange, shading to reduce solar radiation, and supplementary oxygenation. Another, broader and strategic argument made by one Center director, is that adaptive capacities could be enhanced by improving management of risks under current climate variability: ‘‘The DOF always talks about how to adapt to climate change. We talk about water and other relevant systems for production, and having the appropriate policy. They have talked about climate change for a long time. Temperature statistics, water conditions, and how they affect fish. But only a few people think about advanced planning to reduce risk in the case of moderate climate variability. A variable climate is still the most important factor. If we will have to prepare for the future, it is necessary for us to improve our production system so they can respond to climate change.’’ One approach suggested by an official was to work bottom-up, beginning with Centers that perceive they have been impacted by climate variability, and from there inform the DOF who could then create a working group to work on the issue: ‘‘short, medium and long term plans. Every Center would have a plan, which considers expected futures, and prepares responses to immediate extreme events; for instance, flood and drought.’’ Monitoring reports of impacts every 3–5 years would further support adaptation planning. The strength of these bottom-up inputs into planning is that the detailed risks and impacts, and thus solutions vary from area to area. Improvements on treating, storing, extracting, and reusing water in the Centers were seen as an important way to increase resilience to impacts of climate (and other factors) on water resources critical to fish fry production. In some cases, this means investing in waste water treatment ponds and facilities. Technologies, therefore, are expected to play a role in adaptation: ‘‘We may need some technologies such as water temperature reduction technology, and hatching system technology. For drought problems, we will consider high quality wastewater treatment systems.’’ This is consistent with the move toward closed systems, and generally more controlled environments. Centers without easy access to year-round water supplies, in particular, emphasized the importance of increasing water storage during the wet season for use in the dry season, or in some sites, using more groundwater. Several informants speculated that cultured aquatic animals may be able to adapt physiologically—or through

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natural selection—to some aspects of climate change, like increasing temperatures, especially if that change was gradual. Be that as it may, they conceded that there were uncertainties and limits: ‘‘Changing climate little by little would allow fish to adapt, but we will need to monitor how individual fish species have been altered.’’ Breeding programs were also seen to have a role in dealing with shifts in temperature regimes while continuing to develop strains which are resistant to disease and fast-growing. It is recognized, however, that there may be some trade-offs between fast growth rates and robustness to disease and stress. Exploring alternative species should also be part of adaptation: ‘‘Currently, demand for Nile tilapia is high. Would there still be a lot of demand in the future? If yes, we must try to find out how to increase fry by considering good strains that are fast growing’’; if not, then there will be a need to consider new species. DOF officials also suggested the need for more research on the effects of seasons and seasonal changes on the spawning habits of different fish species, especially native species, which may be better able to adapt to environmental changes. Finally, more information about climate change impacts and adaptation options need to be disseminated to stakeholders. IFRD Centers could have a role in sharing information about climate change, in particular, with fish farmers and private hatcheries. According to our informants, however, increasing awareness of climate change issues within the DOF is not yet matched by clear directions on how hatcheries should prepare for change. Robustness of the Proposed Adaptation Options To investigate the robustness of the specific technical options and strategies suggested by informants, we explored their potential performance under the four climate change scenarios (Table 3). Monitoring and information systems or improving disease management are robust options, because they are likely to be beneficial to building resilience to climate under all four scenarios. Increasing water storage and reuse would be most beneficial in a drier scenario and least, possibly a poor investment, in the wetter scenario. Conversely, investment in flood protection measures would be most beneficial in the wetter and the more seasonal scenarios, and less worthwhile in the drier scenario. Adjustment of fry production schedules would be beneficial under all scenarios, but especially the more and less seasonal scenarios. Improved technologies and facilities and new species or strains are costly, so are more likely to be beneficial in scenarios other than the less seasonal scenario with its relatively benign conditions. Relocation of facilities is expected to be the most costly option and probably only worthwhile under wetter or drier

Author's personal copy Environmental Management (2015) 56:859–873 Table 3 The robustness of proposed adaptation options under four climate change scenarios for Northern Thailand

871

Wetter

Drier

More seasonal

Less seasonal

Increase storage or water reuse

???

Flood protection measures

???

Adjust production schedules

Monitoring and information systems

Improved technologies and facilities

Relocation of facilities

New species and improved breeds

Improved disease management

Positive (?) signs indicate an option makes a positive contribution overall under that scenario, whereas a negative (-) sign implies that intervention is unlikely to be worthwhile—costs equal or exceed benefits

scenarios for hatcheries faced with high flood risks or with poor access to water resources. Downscaled model projections for future climate suggest that overall rainfall will increase, especially in the wet season implying increased risks of late wet season flooding (Fig. 3c). The main implication of these analyses is that they suggest, in the long term, that the trend is most similar to the wetter scenario. In practice, however, climate variability is substantial (Fig. 3a), suggesting that it will still be important in coming decades to be prepared for some years and decades which are drier, more, or less seasonal as well.

Discussion Government hatcheries in Northern Thailand produce fish fry to sell to farmers. Hatchery centers have to consider several factors when planning production, including patterns in farmers’ demands, production capacity of the hatchery, local climate, availability of water resources, and overall levels of preparedness to produce individual species. Experiences from earlier years are important to adjusting plans by seasons and to take into account the differences in life history of each species—as has been long recognized within the DOF (Tawaratmaneegul et al. 1994). Weather, climate variability, seasons, and extreme events have significant impacts on aquaculture hatchery production and operations in Northern Thailand. In the cool, dry season, cold weather restricts culture in both outgrowth ponds and in hatchery facilities, especially for Centers located northernmost and at higher elevations. Cold weather results in fewer eggs and higher mortality rates after hatching. Some hatcheries cease production as a result, and others use electric heaters to deal with shortterm cold spells. In Egypt, similar challenges have been met using greenhouses (Nasr-Allah et al. 2014), an idea also discussed in Northern Thailand, but not widely applied. In an extremely dry year, farmers’ demand for fish

fry will be reduced, and breeding and nursery operations may also be affected. Access to reliable supply of clean water is critical for hatcheries. In some Centers, production systems have been modified to become recirculating systems, or to utilize groundwater. Improvements in treating, storing, and reusing water in the Centers were seen as an important way to increase resilience to the impacts of climate (and other factors), on water resources critical to fish fry production. Increasing water demand from other sectors in Thailand could easily exacerbate challenges to hatcheries from a changing climate, as has been suggested by studies in other countries (Das et al. 2013; Hanson and Peterson 2014). Hot weather prior to the start of the wet season, when water resources are often limited, stimulates phytoplankton blooms, high ammonia concentrations, and parasite infestations in hatchery ponds. These represent important water quality and disease management challenges. Hatchery operators believe that a changing climate with more extremes could increase stress on fish fry, making them weak and susceptible to disease. It could also damage production facilities or the quality of key inputs, such as clean water. Extreme high temperatures, or heat waves, reduce tilapia fecundity and also have an impact on hatching and fry mortality rates (Fig. 5). Warmer conditions, overall, would likely shift breeding and spawning periods, and may be beneficial for production of Nile tilapia in the more northerly located Centers during the cooler months. In the wet season, flood risks are an issue in some locations, underlining the importance of adequately protecting hatcheries located in flood-prone areas. In one location, this was solved by building a dyke around the Center, but it came at a high cost. In response, and building on the analysis of robustness of suggestions from informants (Table 3), we highlight three strategies which would enhance adaptive capacities of hatcheries to climate change. First, and with immediate benefits, is to improve the management of climate-related

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risks under current climate variability. The emphasis should be on improving the level of preparedness of hatcheries in dealing with water scarcity during particularly dry years, and extreme flood events in the wet season. In part, this is a water resource management issue, and therefore will require interaction with other non-fisheries stakeholders. Risks to water availability with increasing scarcity and conflicting use have also been identified in previous studies of hatchery sensitivities to climate change: in India (Das et al. 2013), and the US (Hanson and Ostrand 2011). In Thailand, this strengthening of capacities is important to government strategies of promoting Nile tilapia production for export, as it then becomes even more important to sustain production volumes (DOF 2011). Improved management of climate-related risks would help build resilience to climate change more broadly within the sector. Second, is to improve monitoring and information systems, so that rapid, slow-onset, and newly emerging climate-related risks are understood sooner and better by both hatcheries and their farming customers. This is critical to the timely identification of suitable adaptation pathways as climate change unfolds (Wise et al. 2014). Hatcheries currently do not systematically collect information on fecundity, hatching rates, or survival of fry. They also do not regularly monitor water quality or document weather conditions on site. In the short-term, strengthening early warning systems and improving understanding of risks are key. More thorough monitoring and information management would help strengthen hatchery production planning, for instance, in adjusting production schedules to deal with seasonal and inter-annual variability in climate-related risks. In the medium term, systematic monitoring, perhaps within a 3â&#x20AC;&#x201C;5 year cycle, would help build understanding of the impacts of extreme events and climate variability, which in turn could inform adaptation plans to sustain fish fry production. Improved information systems would create opportunities for managing some climate-related risks through better coordination of fry production and distribution among IFRD Centers, as well as plan for relocation (Table 3). Studies of salmon hatcheries in the US have drawn similar conclusions on the importance of monitoring and data collection for adaptation (Hanson and Ostrand 2011). Third, is to undertake research to develop better strains and new species for aquaculture, as well as improve and adapt hatchery facilities and operations. More research is needed on the effects of seasons and climate on the spawning habits of different fish species, and the impacts it has on hatchery production systems. Work also needs to continue in conventional areas such as broodstock management, improving feeds, feeding practices, disease

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management, and water management systems (De Silva and Soto 2009). Short-cycle aquaculture crops using new species, strains, and technologies to fit into seasonal opportunities could be another approach to adaptation (Das et al. 2013). Water re-circulation technologies are already being used in some locations and deserve further development. Hatchery level planning and operations already based on longstanding guiding principles (Tawaratmaneegul et al. 1996) may need to be updated to include climate-related impacts on water management, hatchery operations, and fry demand. Although the empirical focus of this study was on government-run hatcheries in Northern Thailand, the findings of this research and proposed strategies are likely to also be relevant to commercial hatcheries in Thailand at large, as well as hatcheries in other lower, middle-income, or low-income countries with expanding aquaculture sectors. One important difference is that in the private sector, fry prices vary more depending on changes in demand relative to supply. Another is that private hatcheries are under pressure to compete with other providers, and so must market and support their fish fry products. Future research should look at how climate-related risks are managed by private hatcheries.

Conclusion Government hatcheries in Northern Thailand produce fish fry to meet farmersâ&#x20AC;&#x2122; demand and to stock public water bodies. Fry production of tilapia is sensitive to seasonal differences, extreme events, and inter-annual variability in the climate. Hatcheries have some existing capacity to deal with current climate-related risks, but there is less clarity or direction in how they could prepare for climate change. This analysis, drawing on the perspectives of officials in the sector, suggests a couple of promising shorter and medium to long-term strategies that should help make hatchery planning and operations more climate change resilient, these include: improving hatchery operations and management to deal better with risks under current climate variability; improving monitoring and information systems so that emerging climate-related risks are understood sooner and better; and research and development on alternative species, breeding programs, improving water management and other features of hatchery operations. Acknowledgments The work was carried out with an aid of a grant from the International Development Research Centre, Ottawa, Canada, as a contribution to the AQUADAPT project. Thanks to the many students, officials, and farmers who helped with the surveys and expert meetings.

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