Download presentation
Presentation is loading. Please wait.
Published byFelicity Thomas Modified over 8 years ago
1
In 2000, 9 (70%) of 13 amphibian species on the national red list (1 species CR, 3 EN, 2VU, 3 NT following the IUCN critera) In 2005, 6 (<50%) remaining on the red list, and 5 of these 6 species have a better or much better conservation status Improvements due to many years of hard work and where zoos like Nordens Ark have played a major role Combination of monitoring, restoration of habitats, captive breeding and release back in nature within historical range, evaluation, reporting Conservation of threatened amphibians in Sweden Claes Andrén Nordens Ark
2
Reasons for decline Lowering of shallow lakes to get more arable land from 1850 Large scale draining of the open landscape 1940th and 50th In 1960th and 70th followed by large scale draining of forest areas for higher timber production Additionally the quality of remaining water bodies affected by pesticides, fertilzers, heavy metals etc Other consequences of changed land use as in most western countries, such as eutrophication, overgrowing, cease of grazing Ecosystem changes may also change the balance in competion and predation
3
Case studies – What we have done for threatened amphibians in Sweden The Fire-Bellied Toad Bombina bombina, the Natterjack Toad Bufo calamita & the Green Toad Bufo viridis
4
Actions for the Fire-Bellied Toad Bombina bombina
5
Locality for the last Bombina bombina population, Mölle. Died out 1960.
6
Actions for the Fire-Bellied Toad Bombina bombina Population status – trends 1960: Died out 1983: Introductions starts (juveniles) 1990: 25 calling males, 7 breeding ponds, estimated pop size 60 adults Introduction of juveniles contionous 2002: 13 calling males, 5 breeding ponds, estimated pop size 30 adults Restoration of 5 ponds 2004: More than 100 calling males, 6 breeding ponds, estimated po size 400 adults (capture - marking(photo) – recapture)
7
Actions for the Fire-Bellied Toad Bombina bombina Population status – trends Baldringe area Introductions in new localities 1983-85 (300 juv + 200 larvae) 1987-90 (1500 juv) 1998-99 (470 juv) Introductions in total 1983-99 (2 270 juv + 200 larvae)
8
Actions for the Fire-Bellied Toad Bombina bombina Population status – trends Baldringe Status 1990: 64 calling males, 17 breeding ponds, estimated pop size 140 adults 2000: 202 calling males, 32 breeding ponds, estimated pop size 450 adults 2002: 710 calling males, 54 breeding ponds, estimated pop size 1560 adults 2004: 2320 calling males, 93 breeding ponds, estimated pop size 5000 adults 2006: > 3000 calling males, 130 breeding ponds estimated pop size > 7000 adults
9
Actions for the Fire-Bellied Toad Bombina bombina Measured carried out 1. Restoration
10
Ations for the Fire-Bellied Toad Bombina bombina Measured carried out 1. Restoration Mölle 4 restored ponds Gislövs Stjärna 8 new or restored ponds Bäckhalladalen 10 restored ponds Baldringe area > 50 ponds
11
Actions for the Fire-Bellied Toad Bombina bombina Measures carried out 3. LIFE Bombina project Starting 2004, 5 years
12
Actions for the Fire-Bellied Toad Bombina bombina Measured carried out 3. LIFE Bombina project Genetics, sharing experiences and knowledge between Sweden, Denmark, Latvia & Germany
13
Actions for the Fire-Bellied Toad Bombina bombina Visions and goals for the year 2012 One large metapopulation in Baldringe area with 100-150 breeding ponds and 10 000 dults (no further measures necessary) One meta population in Simrishamn area, 30 breeding ponds and 2 000 adults (Measures in four local populations) One population in Mölle fälad (last natural occurrence in Sweden) with 15 breeding ponds and 1 000 adults (Restoring another 10 breeding ponds)
14
Actions for the Natterjack Toad Bufo calamita
15
Skin secretion used in defence
16
Actions for the Natterjack Toad Bufo calamita Biology, environmental demands and threats West European species from Portugal to Sweden and Estonia Estland in north, laying eggs in shallow temporary waters, interesting reproductive biology with individual strategies, breeding from end of April to August (main breeding activity in mid May), adapted to disturbed ground and early succesion stages, prefer sand steppe but also bare rocks, serious threats are overgrowing (ceasing of grazing), eutrophication, competition (Bufo bufo), predation (insects on larvae), draining, exploitation
17
Actions for the Natterjack Toad Bufo calamita
19
Actions for the Natterjck Toad Bufo calamita
20
Actions for the Natterjack Toad Bufo calamita
22
Range and population status – trends West Sweden (Västra Götaland) 46 local populations in the outer archipelago (2004) Lack of information on pop. size, distribution and threats
23
Actions for the Natterjack Toad Bufo calamita Range and population status - trends Smögen – northern most locality for the species (close to Nordens Ark)
24
Actions for the Natterjack Toad Bufo calamita Measures carried out Mapping of local island populations
25
Actions for the Natterjack Toad Bufo calamita Visions and goals for West Sweden (Västra Götaland) In 2006: The species occurs on 46 islands in 13 areas, no estimates of pop sizes Goal for 2012: 10-15 meta populations including groups of smaller islands, each metapopulation with at least 500 adults and 50 breeding ponds (many are high risk ponds)
26
Actions for the Green toad Bufo viridis
27
Actions for the Green Toad Bufo viridis Mating period late April to late May, eggs are layed in shallow waters, usually without vegetation, breeding ponds often influenced by salt water (upp to (0.8%), adults can stand 2% salinity
28
Actions for the Green Toad Bufo viridis Prefer sand steppe but also on bare rocks, serious threats are overgrowing (declining grazing), eutrophication, competion (Bufo bufo), predation and draining Dying larvae in Eskilstorps ängar, the breeding pond is drying up due to draining
29
Actions for the Green Toad Bufo viridis Skåne-Blekinge-Kalmar(Öland)-Gotland Range and population status – trends
30
Limhamns limestone quarry
31
Actions for the Green Toad Bufo viridis Limhamn Limestone quarry Swedens most important Green Toad locality, about 300 adults, regular reproduction, measures taken to secure the population,
32
Eskiltorps ängar
33
Actions for the Green Toad Bufo viridis Falsterbo peninsula 50 years ago the most important locality in Sweden Today < 10 adults within a golf court area, no reproduction Large scale measures to reduce overgrowing vegetation Remaining big problems: eutrofication, polluted drainage and run off water from traffic and settlements
34
Former sandy lagoons at Falsterbo affected by eutrophication
35
Last locality for the Green Toad on the Baltic island Öland, Högby hamn (-96)
36
Actions for the Green Toad Bufo viridis Monitoring of earlier known localities to confirm present status Collecting eggs in the field and rearing in captivity up to sub adults Planning and carrying out restoration actions in destroyed habitats Release of toads in restored areas within the historical range Evaluation and reporting Nordens Ark plays a major role in the In Situ work. In 2006 we are releasing 6-8 000 sub adults toads in four regions in Sweden. Measures carried out
37
Restoration of breeding pond
38
Clearing of reeds in Falsterbo
39
Constructing out door enclosures for metamorphosed Green Toads at Nordens Ark
40
Releasing sub adult Green Toads, Öland Sept -04
41
Releasing sub adult Gren Toads, Öland Sept -04
42
Actions for the Green Toad Bufo viridis 7 populations or meta populations each of at least 500 adults within the historical range Limhamn limestone quarry (Malmö city), coastal meadows SV Skåne (Malmö-Falsterbonäset), coastal meadows and bare rocks E Skåne (Gislövs Stjärna, Gislövs hammar, Brantevik, Bäckhalladalen, Vik), outer archipelago SE Blekinge (Utklippan), Baltic islands Öland and Gotland Visions and goals 2012
43
Thank you
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.