Caesar Kleberg News

TEXAS A&M UNIVERSITY-KINGSVILLE

The Charismatic Reddish Egret

Article by BART M. BALLARD, Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville

Photo by Bart Ballard

Reddish Egrets have two distinct color forms, a dark form with gray body and red head and neck, and one with all white plumage.

Irecall the first time I saw a Reddish Egret foraging in the shallow waters of the Laguna Madre. I was fascinated by its acrobatics as it chased small fish by running, jumping and flapping about. The array of foraging behaviors was quite different from the “sit and wait” behavior used by most wading birds. This charismatic nature is a distinguishing characteristic of the Reddish Egret in the field and one that I have come to admire over my years of studying them.

There are two color forms of the Reddish Egret that look quite different and in which the novice observer would assume to be two different species. The more common dark form exhibits grayish plumage with a reddish head and neck, and a white form has entirely white plumage.

Both color forms can be distinguished from similar looking egrets by their pinkish bill with black tip and their very animated foraging behavior. The dark form is more common in northerly portions of the species distribution, and the white form becomes more common throughout the Caribbean. Although breeding pairs typically include a male and female of the same color form, we commonly see breeding pairs with both a dark color form and white color form.

Like many wading bird species, the Reddish Egret experienced a severe population decline because of unregulated harvest by plume hunters in the late 1800s and early 1900s. The ornamental feathers of wading birds used in their courtship displays (often called plumes) were sought to adorn women’s hats during that time.

By the early 1900s, the Reddish Egret was nearly extirpated from the United States. Although the species has partially recovered from the impacts of plume hunting, its population remains well below historic numbers.

Due to its rarity and complete reliance on coastal wetlands, the Reddish Egret has been designated as a threatened species by the state of Texas, a species of concern by the U.S. Fish and Wildlife Service, and endangered in Mexico. The Reddish Egret remains the rarest species of wading birds in North America, with a population of approximately 2,000 pairs.

Until recently, very little research had been conducted on the Reddish Egret and much of its ecology was unknown. However, the Caesar Kleberg Wildlife Research Institute

Sponsored by JOHN AND LAURIE SAUNDERS

has invested considerably over the last 15 years to increase our knowledge of this understudied species to better inform conservation efforts. Along with collaborators from state and federal agencies, as well as non-government organizations, we have learned much about this species in a relatively short amount of time.

The Reddish Egret has a partial migration strategy, which means that a portion of the population is resident and remains near breeding areas throughout the year, while the remainder of the population migrates to more southerly wintering areas. Their partial migration strategy likely results from a decline in the amount of foraging habitat during winter due to changing water levels from seasonal tides. Also, some of the fish species they prey on become less abundant during winter. As a result, a portion of the population leaves to find areas where food is more abundant.

Our research shows that about 25 percent of the birds breeding in the Laguna Madre of Texas migrates to southerly wintering areas. We marked adult Reddish Egrets with automated tracking devices and monitored their movements across several years.

Most Reddish Egrets migrating from the Laguna Madre travel south along the Gulf Coast of Mexico and cross the Isthmus of Tehuantepec to winter on the Pacific Coast of Mexico in the states of Oaxaca and Chiapas, as well as into the countries of Guatemala and El Salvador in Central America. This is a one-way trip of up to 1,400 miles.

Interestingly, migratory individuals show high philopatry to wintering sites; in other words they tend to return to the exact same location each winter. Several of our Reddish Egrets marked with tracking devices not only returned to the same coastal estuary on Mexico's Pacific Coast, but also to the same section of the coastline within the estuary.

Reddish Egrets cannot make the entire migratory trip from the Laguna Madre to wintering areas without stopping. Thus, they use stopover sites to rest and refuel so they are able to make the next leg of their migratory journey.

A stopover site's quality is critical for migratory individuals to obtain the energy needed to continue on with their journey. Also, the location of a specific stopover site along the migratory route influences its importance because some occur in areas where egrets are able to rest and feed following a long migratory flight.

We found that Reddish Egrets used several estuaries along the Gulf Coast of Mexico during both autumn and spring migrations. However, one site in particular was the only site used by all migratory individuals and proved to be the most important stopover site for Reddish Egrets during migration. Laguna San Andres is located north of Veracruz, Mexico and is a site we have identified as especially important to migratory Reddish Egrets. This lagoon was often the first stop after a long, overland flight from the Pacific Coast across the Isthmus of Tehuantepec.

Our research of the Reddish Egret has covered all portions of the annual cycle and has provided information about many previously unknown aspects of its ecology. We have documented the genetic structure of the Texas population, investigated the ecology and survival of juveniles following fledging, mapped their foraging habitat in the Laguna Madre, identified important migratory stopover sites, documented wintering areas of migratory individuals, and assessed factors influencing reproductive success for migratory individuals, to name a few. Together, this information provides a solid foundation to support conservation efforts for this charismatic species.

Recently, an international collaboration has formed to develop a concerted conservation strategy to help understand current threats to the Reddish Egret, integrate recent research findings into conservation actions and understand other types of information needed to effectively manage Reddish Egret populations.

NOBLE RESEARCH INSTITUTE

Grazing Animals

Instrumental in Developing Clean Water Through Healthy Soil

Article by JOSH GASKAMP / Noble Research Institute wildlife and range consultant and MEREDITH ELLIS / rancher, G Bar C Ranch in North Texas Photos courtesy of MEREDITH ELLIS

Clean water is closely tied to the health of our plant communities and soil resource, but a common misperception is that plants and soil can contribute to poor water quality.

In reality, plants and soil are not the problem. The impacts of improper management are revealed through changes/losses in plant communities and soil erosion.

Soil erosion, excessive runoff, overabundant aquatic plants and unwanted fish species are commonly blamed for muddy or turbid water bodies. While these factors are sometimes the cause of poor water quality, the more common underlying causes are mismanagement in the watershed and allowing livestock to have access to surface water interfaces. In fact, increased runoff and overabundant aquatic plants are symptoms of poor watershed management and an ineffective water cycle.

The agriculture industry often gets blamed for degraded ecological conditions of watersheds due to the lack of grazing management and livestock placement. But have you ever considered how agriculture and, more specifically, livestock are key to the development of healthy soil, healthy plants and clean water?

There are six principles of soil health: • Know your context • Cover the soil • Minimize disturbance • Increase plant biodiversity • Maintain continuous living plants/roots • Integrate livestock

One of the six principles of soil health is integrating livestock. Wild grazing animals were an essential part of building soil, maintaining plant diversity and ensuring a functional water cycle in our rangelands long before us.

Certain conventional agricultural practices have diminished the soil’s capacity to function as it did before European settlement. But our soils can and are being rebuilt with management based on these six principles.

Unlike a recipe, we don’t just add livestock and expect the soil to improve over time. On the G Bar C Ranch, Meredith Ellis grazes each pasture depending not only on the cattle herd's nutritional requirements but on daily rotational decisions made with the help of the six principles of soil health.

In a cow-calf operation that must remain incredibly flexible, the one rigid guideline she imposes is to always abide by those principles. This includes knowing each grass type and ecological zone in which the cattle are grazing.

For example, in Meredith’s operation, grazing cool-season grasses off of coastal Bermuda in late spring allows cattle to deliver additional nutrients through manure and urine to invigorate the Bermuda. By removing the cool-season grasses, the cattle clear the way for sunlight to reach the Bermuda prompting it to grow more vigorously during its growing season in the warmer months.

Grazing of native pastures requires close observation as well. During the early summer, cattle lightly graze adding nutrients

To learn more about how Noble Research Institute supports agricultural producers through research, education and direct consultation, visit www.noble.org.

and incorporating dead biomass into the soil. The cattle are not returned to the native pastures until the late fall when the native grasses have matured and formed seed heads, making the cattle’s role at this time of year one of interring seeds into the soil for the next growing season. Grazing in this manner is improves the health and resilience of the landscape in which the cattle are grazing.

The sixth principle teaches us to apply purposeful and adaptive grazing and that the soil and plants will respond. We must manage timing, intensity, frequency and duration of grazing and make observations and adjustments along the way to build soil that grows healthy and diverse plant communities— and infiltrates water.

The following are five of our favorite concepts in grazing management: • Use the shortest possible grazing period • Use the highest animal density possible • Feed half of the standing forage to the soil • Overgrazing is a function of time, so allow grazed plants to completely recover • Be adaptive

We don’t know all of the roles livestock play in soil health, but we do know that they contribute to natural fertility and microbiology in the soil by spreading urine and feces; they trample and lay forage down on the soil to integrate organic matter; and they create a natural disturbance that stimulates plant diversity, growth and vigor.

Healthy soil infiltrates and holds more water, making it not only more resilient in drought but protecting the watershed from erosion in flood. Healthy soil acts as a sponge pulling water in rapidly. Groundwater infiltrated into healthy soil replenishes aquifers, allowing springs to flow again.

Ellis knows the role that a healthy plant community plays in water quality downstream. Thriving communities of native grasses reach deep into the soil, allowing for greater water holding capacity and making her land more drought resistant and resilient. In turn, any excess water emerging from hillsides seeps in and emerges crystal clear, eventually entering larger bodies of water downstream.

The G Bar C Ranch consists of 6 percent cropland used for grazing and the operation is going on its third year of planting warm-season cover crops specifically for soil health. In the scorching summer heat, these pastures now include a mix of several species shading the soil, preventing wind and water erosion, increasing water holding capacity and allowing for extra grazeable forage during that time. What was once bare ground during those months now acts as an additional water filter downstream on the operation while building upon the soil's health.

In properly grazed watersheds, trampled or standing plants continue to break apart water droplets from rainfall. This allows any water that does flow over the land to slow down and be filtered by abundant plants.

Because high stock density can be a problem near ponds, good managers often fence out ponds with the exception of a single access point. Livestock can drink, but not linger in and around water interfaces. This no-graze buffer allows any water flowing over the land to be adequately filtered by plants before reaching the pond.

Previous generations of conventional ranchers managed livestock and associated watersheds as a commodity. Their cattle could turn a finite amount of grass that the land produced each year into beef, but productivity and profit fell over time.

Today, ranchers are wanting to be more regenerative and profitable. Successful ranchers are using livestock as a tool to improve soil and ranch productivity for years to come while providing public benefits through biodiversity, clean air and clean water.

Ellis sees her role as a rancher as one that responds to her changing environment and uses her cattle as a tool to invigorate the land. The cattle on her ranch are constantly moving through 58 pastures, mimicking the bison that grazed these historic prairies for millennia. The land, as a result, benefits because of the presence of ruminant animals, not in spite of them, and is a key factor in maintaining the health of the ecosystem in which they co-evolved.

The all-encompassing benefit of abiding by the six principles of soil health, as seen on the G Bar C Ranch, is that the land is resilient and able to withstand ever-increasing climate events such as drought and flood, adding to the health of not only the cattle but of the landscape.

Smooth Cordgrass

A Smooth Operator

Article by ERIC GRAHMANN and STEVEN GOERTZ Photos by STEVEN GOERTZ

Around the perimeters of Texas' bays and estuaries, smooth cordgrass is one smooth ecological operator. Arguably, no plant species holds a more important role in providing wildlife habitat and stabilizing Texas’ saltwater shorelines.

Also called saltwater cordgrass or saltmarsh grass, Spartina alterniflora is a perennial that spreads via thick yellowish/ white rhizomes, lateral underground stems rooting at intervals, through the mud. The stems and leaves are smooth, and the leaves terminate in a spiny point.

The importance of this grass for intertidal wildlife is huge, as it provides food and cover for a wide variety of species. These include algae and detritusconsuming invertebrates such as snails, shrimp and crabs and larger species such as King and Clapper Rails. Cordgrass colonies are incredibly important fish nurseries, harboring juvenile southern flounder, red drum and Atlantic croaker, among many others.

Every seasoned backwater angler has witnessed red drum slowly prodding the nooks and crannies of the outer periphery of smooth cordgrass colonies for prey. It’s an indicator species to the brackish marsh many migratory and non-migratory wildlife species rely on. The leaves are seasonally/ occasionally eaten by gritty coastal cattle and nilgai.

No plant does more to protect bayside shorelines and adjoining terrestrial plant communities. This species is often the first (and sometimes the only) line of defense in softening the effects of waves generated via wind and wake.

Smooth cordgrass is simply invaluable in maintaining the shoreline integrity of Texas bays, making it a tremendous ecological operator.

Oh, and economics! Think of the numerous coastal properties protected from erosion by this species. Its value to coastal Texans is simply tremendous.

Smooth sailing!