Trials and tribulations of grassland waders
Dr Jennifer Smart – Principal Conservation Scientist
The cast of waderologists..
Mechanistic research on reserves
Detailed studies on reserves?
this?
or this?
More wet features equals more waders
Redshank density
1.25 1
0.75 0.5
0.25 0
Eglington et al (2007) Restoration of wet features for breeding waders on lowland wet grassland. Journal of Applied Ecology, 45, 305-314.
0
50
100
150
200
Total wet feature length (m)
250
Smart et al (2006) Grassland-breeding waders: identifying key habitat requirements for management. Journal of Applied Ecology, 43, 454-463.
Distance to footdrain flood (m)
Lapwings choose to nest close to FDs 70 60 50 40 30 20 Random
Nest
Eglington et al (2007) Restoration of wet features for breeding waders on lowland wet grassland. Journal of Applied Ecology, 45, 305-314.
Joiner, C. (2002) Management of wet grassland for breeding waders: are wet features important for the Northern Lapwing, Vanellus vanellus? MSc thesis, UEA.
Wet features are important for chicks
Eglington et al (2010) Managing water levels on wet grasslands to improve foraging conditions for breeding northern lapwing Vanellus vanellus. Journal of Applied Ecology, 47, 451-458.
and not just for lapwing chicks‌‌
Close to water
Vegetated ground Good % tall vegetation
Smart, J. (2005) Sea-level rise mitigation strategies for breeding redshank in East Anglia. PhD, University of East Anglia.
Wet features are good sources of chick food
Eglington et al (2010) Managing water levels on wet grasslands to improve foraging conditions for breeding northern lapwing Vanellus vanellus. Journal of Applied Ecology, 47, 451-458.
Joiner, C. (2002) Management of wet grassland for breeding waders: are wet features important for the Northern Lapwing, Vanellus vanellus? MSc thesis, UEA.
Mean condition index
Wet features improve condition and survival
Eglington et al (2010) Managing water levels on wet grasslands to improve foraging conditions for breeding northern lapwing Vanellus vanellus. Journal of Applied Ecology, 47, 451-458.
Other advantages of wet features Diameter = 100m Area = 0.79 ha 398 m ha FD length = 200m Diameter = 50 m Area = 0.24 ha 1889 m ha
Other advantages of wet features
765 m ha
Predation rears its ugly head again!
Nest success
Productivity
0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
R.I.P – Reducing impacts of predators SWARD FIELDS 77B
WET FIELDS
Control Sward Wet
R.I.P – Reducing impacts of predators 0.9
0.8
0.8
Hatch success (±95% CI)
0.9 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0
0.7 0.6 0.5 0.4 0.3 0.2 0.1 0
Control
Veg
Wet
0.9
0.8
0.8
Hatch success (±95% CI)
0.9 0.7 0.6 0.5 0.4 0.3 0.2 0.1
2008
2009
2010
2008
2009
2010
0.7 0.6 0.5 0.4 0.3 0.2 0.1 0
0 Control
Veg
Bodey et al (2010) Reducing the impacts of predation on ground-nesting waders: a new landscape-scale solution? AAB 100, 167-174.
Wet
Cole, T. (2010) Reducing the impacts of predation on ground-nesting waders: a new landscape-scale solution? MSc Wildlife Management and Conservation Reading.
Becky’s PhD – starting to scale up VERGES influence wader nest predation rates Lapwing predation probability
Higher predation of nests far from verges.
Verge outside field
Laidlaw et al (2013) Managing a food web: impacts on small mammals of managing grasslands for breeding waders. Animal Conservation, 16, 207215.
Distance to verge (m)
Laidlaw et al (2015) The influence of landscape features on nest predation rates of grassland-breeding waders. Ibis, 157, 700-712..
WATER influences wader nest predation rates Dry fields
1.00
Lapwing predation probability
0.75
0.75
0.50
0.50
0.25
0.25
0.00
0.00 0
50
Wet fields
1.00
100
Distance to field edge (m)
150
0
50
100
150
Distance to field edge (m)
Laidlaw et al (in review) Scenarios of management options to reduce predator impacts on nesting waders in wetland landscapes. Journal of Applied Ecology.
WADERS influence wader nest predation rates 1.00
Lapwing predation probability
0.75 0.50 0.25 0.00
0
3
1.00
Redshank predation probability
6 Lapwing density
9
0.75 0.50 0.25 0.00
0
2
4
Lapwing density
6
8
Laidlaw et al (in review) Scenarios of management options to reduce predator impacts on nesting waders in wetland landscapes. Journal of Applied Ecology.
By how much can land management alter predation?
Lapwing predation probability
1.0 0.8 0.6 0.4 Wetter
*
*
*
*
Drier Drier Drought Drought Drought Drier Drought Remove Corridor Add Wetter Wetter Wetter Drier Remove Corridor Addition Remove Corridor Addition Remove Corridor Addition
A ~20% reduction in predation is possible, but only if management is highly targeted to areas of high density.
Laidlaw et al (in review) Scenarios of management options to reduce predator impacts on nesting waders in wetland landscapes. Journal of Applied Ecology.
From nature reserves to landscape Landscape nests: 486 Reserve nests 258
From nature reserves to landscape
Laidlaw, R.A., Gill, J.A. & Smart, J. (2015) Reducing the impacts of predation on breeding waders using landscape-scale habitat management. RSPB & UEA, Defra Research Report on Project LM0301.
What next?
Experiment
Large-scale – 3 yr exp Fences - manipulate synchrony & density Effects - nests, chicks, recruitment and foxes
X
Thanks…….