Ch. 14: Zoos and Gardens

Ex Situ Conservation Ex situ: outside of a species’ habitat Historically, zoos and gardens were an entertaining diversion for the wealthy Now goals include educating general public gaining support for biodiversity conservation scientific research

The ark metaphor 24 species of plant and 36 species of animal exist only in captivity Captive populations may be an insurance program in case of extinction in the wild Some species went extinct in captivity and others may never be kept in captivity

Studbooks and Pedigrees Avoid artificial selection ~ don’t want to domesticate them, want to release them into the wild or keep two breeding stocks, one for reintroduction, one for captivity Want to avoid inbreeding, but record keeping when siblings are in different institutions is complicated. use studbooks and pedigrees, usually one per species Logistics of maintaining genetic diversity shipping breeders from one zoo to another transferring embryos using domestics as surrogates calculating mean kinship ~ identify individuals who are more different

Storing Biodiversity Some life-history stages are easier to keep ex situ than others Microbes ~ freeze-dry samples easier to store than culture don’t have to worry about evolutionary changes in culture Animals ~ cryopreservation of semen and embryos common for domesticated species, beginning for wild ones Plants ~ many seeds easily maintain viability but viability decreases over time, so occasionally grow-out seeds to get new ones. otherwise, retain pollen, plantlets, tissue samples common for domestics, but wild species representation increasing Genetic Material ~ tissue for DNA extraction, DNA

Conservation of Domestics Few species dominate our diet, but several different varieties plants may be called cultivars animals usually called breeds Ideally crops are high yield, don’t require pesticides, herbicides, too much water, fertilizer or anything else landraces: local varieties that do well in local conditions but often not high yield International repositories for different plant varieties Maintenance of local breeds becoming a hobby of ranchers but wild ancestors of domestic animals generally overlooked as source of diversity

Ex Situ – In Situ Interface Zoos and gardens are not a replacement for natural ecosystems Reintroductions are often unsuccessful to date, no self-sustaining populations Not all captive animals were born in captivity remove individuals for use in zoos and gardens remove individuals because low chance of survival in wild what about when this means removing breeding individuals from a threatened, but breeding population? Shift from exhibiting the most species to exhibiting species who can best benefit from captive breeding programs but resources often directed toward most popular exhibits

Ex Situ Conservation is Controversial Just let species go extinct with dignity? Easier to augment with captive breeding than mitigate threat? Spending time and money on husbandry and captivity rather than on the ground conservation and management? But still does good things Increasingly involved in advocating for conservation and funneling money to in situ conservation If in situ conservation is successful, zoos and gardens stop being a Noah’s arc and focus on education and outreach

But it has supporters Increasingly involved in advocating for conservation and funneling money to in situ conservation