1 / 32

Reintroductions

Reintroductions. Australian and New Zealand perspectives Canadian reintroductions Case studies The good, the bad and the ugly?? Other issues to consider. Australia. 100+ species of plants and animals have gone extinct in the last 200 yrs Mammals 25 species extinct

yen
Download Presentation

Reintroductions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Reintroductions Australian and New Zealand perspectives Canadian reintroductions Case studies The good, the bad and the ugly?? Other issues to consider

  2. Australia 100+ species of plants and animals have gone extinct in the last 200 yrs Mammals 25 species extinct 10 species only on islands 17 species in remnant habitat 10% of their pre-European range

  3. Australia Medium and large species are more vulnerable to extinction Fig 1 Cardillo and Bromham 2001

  4. Reintroductions in Australia Many macropod reintroductions have been attempted Success rate Islands no predators 82% Mainland/island with predators 8% Failure attributed to predation - foxes and cats Short 1992

  5. Reintroductions in Australia • PREDATOR FREE ISLANDS • Eg Faure Island Sanctuary, WA • 2002 Burrowing bettong 20 released now 100 • Shark Bay Mouse 100 released now all over island 2005 Banded hare wallaby 16 released “thriving”

  6. Faure Island 6000 ha

  7. What about the mainland? Australian Wildlife Conservancy Triple barrier sanctuaries Predator control Predator removal release Woylie Karakamia Sanctuary fence 12 km buffer zone

  8. Reintroductions in Australia Basic premise Limit the impact of predation IMPACT = NUMBER X EFFICIENCY Options Lethal Control Fertility Reduce Primary Prey Eg Flinders Range Rabbit haemmorhagic disease Rabbit population down 85% Fox and cat population down 40%

  9. Limit the impact of predation IMPACT = NUMBER X EFFICIENCY Options Pre-release training Aversion therapy Enhance refuges Stokes et al.2004 Wire net

  10. Limit the impact of predation Refuges from predation Wire net Wire net Giving up densities Foraging path Stokes et al.2004

  11. New Zealand Area of NZ - 27 million hectares Area not invaded by exotics 2000 ha No terrestrial mammals prior to humans But 245 spp birds 71 % endemic Early Extinctions 33 Post-European extinctions 19 Cause - exploitation - invasive spp - 33 mammals

  12. Conservation in New Zealand Step 1 % conservation budget - 40% Area where exotics eradicated 30,000 ha Islands > 55 ha: 53 one spp removed 36 free of all introduced spp

  13. Reintroductions in New Zealand Examples Black robin 1977: 1 female 1994: 200 Giant weta 2001: 81 released 2003 - producing young Tuatara 1996-2004 Releases on 4 islands Number translocations >400 Number animal taxa - 68 +

  14. Reintroductions in New Zealand Restoration aims recreate structure, function and dynamics of original ecosystem What do you do if keystone spp is extinct? Norfolk island - 2 extinct pigeons Chatham Island - extinct parrot

  15. What do you do if keystone spp is extinct? Consider use of a “functional surrogate”

  16. Reintroductions In Australia and New Zealand • Common tool to • reduce extinction risk of vulnerable species • - restore degraded ecosystems • Key factor: removal/control of predators • Why? • Introduced predators are the major cause of population declines

  17. Exploring reintroductions In Canada Why? 1) 577 Species at Risk 70% of Recovery Plans consider translocations • Climate Change and possible need to re-assemble communities

  18. Reintroductions: the good?

  19. Reintroductions: Burrowing Owl

  20. Reintroductions: Burrowing Owl Population < 1000 pairs in Canada declines 22%/yr Issues - habitat loss - lack of burrows - shortage of food - vulnerability to predators - migration - fewer refuges - wintering grounds ??????

  21. Reintroductions: Burrowing Owl In BC Attempt 1 1983-1989 Vaseaux/Osoyoos Lake Wild ct breeding pairs released in artificial burrow Produced young But no birds returned to site FAILED

  22. Reintroductions: Burrowing Owl In BC Attempt 2 1990 - now Thompson/Nicola Captive breeding in Vancouver/Kamloops 1 yr old birds released at historical sites artificial colonies created by volunteers

  23. Reintroductions: Burrowing Owl

  24. Reintroductions: Burrowing Owl Attempt 2 - owls breed, migrate and return - population small but increasing Additional benefits ongoing research on captive breeding public outreach and education landowner support for initiative modified grazing regimes improvements to grassland habitat

  25. Reintroductions: Vancouver Island marmot Numbers in wild 1984 235 102 71 2000 36 Distribution 25 sites on 13 mountains; 67% of animals on 4 mountains

  26. Vancouver Island marmot Occupy small patches of sub-alpine meadow Patches available but no longer colonized Issues: logging and clearcuts predation disease climate change (snowfall/snowpack)

  27. Reintroductions: Vancouver Island marmot 1997-1999 17 removed for captive breeding 1999-2004 38 more removed 2008 4 facilities - 160 animals Releases 2003 4 (all 1-2 yrs - all dispersed -- >killed) 2004 9 (6 m 3 f; all 2 yrs) 15 (10 m 5 f; all 2 yrs)

  28. A marmot update 2008 total releases = 155 11 litters born 7 litters with 1+ captive parent

  29. A marmot update 2003 2008 Captivity 77 162 Wild 21 102 Mountains with Marmots 4 17 Possible pairs 3 17+

  30. Summary Reintroductions Are an increasingly common tool Are successful if the cause of declines are known and eliminated/reduced Are less successful if the reasons for declines are uncertain

  31. Genetic issues in reintroductions • Where do we get individuals from? Natural selection ---> local adaptation To far away ---> hybridisation/outbreeding depression • 2. How many founders are needed? Too few --> low genetic diversity and inbreeding depression?

  32. Practical issues in reintroductions • How and whom to release? • Soft or hard introductions • Age/number/relationships of individuals

More Related