A look across the borders: protection of farmland birds in wet grasslands in The Netherlands

Transcription

1 A look across the borders: protection of farmland birds in wet grasslands in The Netherlands Maja Roodbergen Wolf Teunissen

2 Trends of meadow birds Numbers of meadow breeding waders have declined since 1960s

3 Trends of meadow birds Yearly change -10% -5% 0% 5% 10% 15% Höckerschwan Brandgans Schnatterente Krickente Knäkente Löffelente Tafelente Reiherente Rebhuhn Wachtel Austernfischer Kiebitz Bekassine Uferschnepfe Großer Brachvogel Rotschenkel Feldlerche Wiesenpieper Schafstelze

4 Distribution of meadow birds low high

5 Farmland grassland arable land

6 Intensification of agriculture mowing frequency

7 Meadow bird protection in the Netherlands Meadow birds in Netherlands: >40% of European Black-tailed Godwit (Uferschnepfe) >25% of Oystercatcher (Austernfischer) >10% of Lapwing (Kiebitz) Protection 1) Protection of nests by volunteers (AES and voluntary) 2) AES: mainly nest protection and postponed mowing (until 23 May or 1,8,15 or 22 June) 3) Reserves

8 Meadow bird protection in the Netherlands Nest protection, AES and reserves Nests found 2008 Lapwing Black-tailed Godwit Oystercatcher Redshank Other waders Ducks and geese Other birds Songbirds Total

9 Meadow bird protection in the Netherlands AES reserve regular

10 Meadow bird protection in the Netherlands AES Pros: Large area Support from farmers for nature conservation Positive effect of biodiversity on agriculture Aesthetics (landscape) Many farmland species declining Cons: Relatively few rare species No clear targets Low effectiveness

11 Effectiveness measures (Van Egmond & De Koeijer, 2006) 80 index regular AES reserves number of species regular AES reserves

12 Effectiveness measures Number of breeding pairs x 1,000 regular reserves AES

13 Nest protection Unprotected nests: increased losses due to agriculture and predation (Teunissen et al., 2005) Lapwing Black-tailed Godwit 4 5 Daily loss (%) ,9 1, Daily loss (%) ,4 6,

14 Nest protection Fate of nests Importance Successful 54% Predation 24% Agricultural activities 7% Desertion 5% Cattle 2% Other 2% Unknown 6% Predation index 2000 N = 90,000 clutches Predation rate 24%

15 Nest protection Daily survival rate 1,0 0,8 0,6 0,4 0,2 0,0 Black-tailed Godwit Normal Grazing Mowing Manure Fertilizing Not protected Protected

16 Nest protection Observer effects (Goedhart et al., 2010) Observer effect (h) Black-tailed Godwit Lapwing Mean predation rate (24%) High predation rate (45%) 1.3% 3.5% 15.5% 11.0%

17 Nest protection 100% 80% Black-tailed godwit, high predation rates Daily survival rate 1,0 0,8 0,6 0,4 0,2 0,0 Normal Grazing Mowing Manure Fertilizing Not protected Protected Hatching success 60% 40% Not protected 1 visit 2 visits 3 visits 20% 0% Normal 3 days of grazing Mowing Manure Fertlizer

18 Low effectiveness AES (partly) due to Observer effects at high predation rates Successful nests in intensive grasslands have lower chick survival; ecological trap? (Kentie et al., 2012) Postponing mowing seems to help, but still low chick condition and survival in intensive fields 43% of AES situated in unfavourable areas (low densities, traffic, low water levels, high predation rates, openness landscape, Melman et al., 2006)

19 Improvements Nest protection: As few visits as possible, only when nest is threatened In areas with sufficient chick habitat Postponed mowing: In combination with extensive management Location: Only in suitable areas AES should be concentrated in extensive areas with high water tables

20 New approach: core areas Source areas Minimum breeding densities Adequate long-term management Good conditions in surrounding landscape (high groundwater levels, openness) Example Black-tailed Godwit (Teunissen et al., 2012)

21 Conditions Openness Openness (m) Declining Stable

22 Conditions Mowing date But mean mowing date in NL 5 May Mean mowing date 20 May 5 June Declining Stable

23 Conditions Ground water level Dependent on soil type Ground water level (cm) Declining Stable

24 Possible areas Interconnected areas with densities >30 bp/km2(red) or >15 bp/km2 (blue)

25 Possible areas Openness >400m required (green and blue)

26 Possible areas Mean mowing date >21 May (yellow-green)

27 Possible areas Ground water level <40 cm (dark blue)

28 Possible areas Resulting probability of positive trend

29 Possible areas Overlap with other species (% of populations within potential core areas for Black-tailed Godwits) Species >15 bp/km 2 (%) >30 bp/km 2 (%) Shoveller 39,9 16,1 Tufted duck 15,2 5,1 Oystercatcher 25,6 8,5 Lapwing 20,2 7,8 Black-tailed Godwit 51,0 20,0 Redshank 34,2 13,8 Skylark 13,7 5,3 Meadow Pipit 13,2 4,2 Yellow Wagtail 2,6 0,7

30 Core areas meadow bird landscape (potential for core areas with buffer) potential for core areas meadow bird core area Management aimed at critical meadow birds

31 Recommendations High ground water levels Low fertilisation levels Late mowing and large spread in mowing dates Nest protection only when necessary In concentrated areas with favourable conditions

32 Future developments in policy Decentralisation of conservation efforts Implementation of new Common Agricultural Policy of EU