EEB 2208 LECTURE TOPIC 16 EX SITU CONSERVATION, RELEASE PROGRAMS. Reading for this lecture Primack: Chapter 14

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1 EEB 2208 LECTURE TOPIC 16 EX SITU CONSERVATION, RELEASE PROGRAMS Reading fr this lecture Primack: Chapter Intrductin A) DEFINITIONS i) In situ cnservatin means that the cnservatin activities ccur where the species naturally ccurs in the wild. Ex situ cnservatin means that actins are taking place that invlve remving the species frm its natural setting. B) WHEN IS EX SITU CONSERVATION USED? i) Ex situ cnservatin is usually used as a last resrt, when a ppulatin has becme s small r s endangered that extinctin is cnsidered inevitable withut extreme interventin. E.g., Califrnia cndr (nw reintrduced). Smetimes ex situ cnservatin is the nly chice, because a species n lnger exists in the wild. E.g., Père David s deer see the text bk. 2. Where des ex situ cnservatin ccur? A) ZOOS, WILDLIFE PARKS, PRIVATE COLLECTIONS, AQUARIUMS, ETC. i) Over 7,000 vertebrate species are kept in zs wrldwide. A number f endangered invertebrates (e.g., Pacific island snails) are als kept in captivity. Fr the mst part, hwever, the species represented in zs are a biased subset f all species, typically emphasizing species that are big and i charismatic. Zs are relatively gd places fr maintaining species in captivity and fr captive breeding prgrams, because they already have large facilities geared twards keeping a wide variety f species and a trained staff with husbandry skills geared twards unusual species. Since zs have an ecnmic functin they are als in a gd psitin t take advantage f captive breeding prgrams and use them t generate sme f the mney that keeps the prgram ging. Prbably the majr cnservatin functin that zs play is captive breeding. Many techniques are used in captive breeding, ften speciesspecific. In mst cases, hwever, these methds are fcused n the simple gal f increasing reprductive utput and the survival f ffspring. A few examples include: crss-fstering & duble-clutching in many species the reprductive rate can be increased by taking yung (r eggs) away frm their parents, s that the parents start t breed again mre rapidly. One slutin fr what t d with the remved yung is t give them t a clsely related species t raise. humans raise yung anther slutin is fr humans t hand-raise them. This is usually less preferred, because it can be extremely time cnsuming, but ften it is necessary (see whping crane example, belw). artificial inseminatin in sme cases, pairs are reluctant t mate; increasingly this prblem is being slved by taking sperm frm the male and artificially inseminating the female. This technique can als be useful if ne wants t determine exactly which individual mates with which, which can be helpful in zs as a way f limiting the 1

2 effects f inbreeding (see ntes n studbks belw). A third case when this methd might be useful is when several zs want t pl their animals t increase the size f the verall ppulatin: mving vials f sperm arund between zs is easy, whereas mving animals arund ften is nt. embry transfer t surrgate mthers anther way f increasing the number f yung prduced is t create test-tube babies and then implant them int surrgate mthers. Smetimes these mthers can be f different thugh clsely related species. crygenics, clning, etc. as technlgies develp, sperm, eggs and embrys are being frzen and kept n ice fr future use. Clning has als been prmted as a ptential way t help endangered species t reprduce. The science f clning, hwever, is at a very early stage and many prblems need t be vercme befre it becmes a viable slutin fr mre than a few islated cases. pedigrees, studbks a mre traditinal, thugh exceedingly effective, tl is the maintenance f studbks t keep track f hw individuals are related t each ther. By cnstructing a family tree and ding a pedigree analysis it is pssible t minimize the relatedness f individuals wh mate. By ding this, inbreeding can be kept t a minimum. With the increasing use f artificial inseminatin, it has becme even easier t determine hw individuals are paired and t maintain maximally utbred ppulatins. mving animals arund (artificial dispersal) finally, when sperm transfer is nt an ptin, it is pssible t mve individuals arund t help reduce inbreeding within each small z ppulatin. iv) Example: The guar is an endangered wild x frm Asia. Researchers have used the species t develp and experiment with many f the techniques described. In 2001, the first clned guar was brn. This individual was implanted int a surrgate mther f a different species (a cw). v) Example: The whping crane is an endangered bird that breeds in Canada and winters in Texas. Only a few 100 are left in the wild, but there is a grwing captive ppulatin. Duble-clutching can be dne, but raising the yung can be difficult withut their parents. Initially a different species (sandhill crane) was used t incubate and raise the yung. But the baby whping cranes imprinted n their surrgate parents and sme subsequently chse t mate with sandhill cranes. When humans raise the yung, imprinting is als a prblem, s peple have t dress up like adult whping cranes whenever they interact with the yung birds t prevent them frm getting t mixed-up. B) IMPROVING HUSBANDRY i) Sme species d nt survive r breed well in captivity. Cnsequently, new husbandry techniques cnstantly need t be develped fr these prblematic species. Different facilities vary greatly in their quality. Cnsequently, there is a lt f variatin in hw well species d in different settings. Sme places have made the breeding f endangered species a majr part f their missin and have devted cnsiderable resurces t captive breeding prgrams. But nt all facilities have such a strng cmmitment r the resurces t fllw thrugh. i There is als variatin in the needs f different species and althugh there is a lt f institutinal knwledge (i.e., the knwledge f individual practitiners), there are relatively few detailed studies that attempt t understand hw captivity affects particular species. 2

3 iv) One such study shwed that species with large hme ranges in nature (e.g., plar bears) tend t d wrse in captivity (i.e., they had higher infantmrtality, and were mre prne t shw repetitive behavirs assciated with stress, such as cnstant pacing). Studies like this can help prvide ideas fr hw t imprve the z envirnment fr susceptible species. C) BOTANICAL GARDENS, ARBORETUMS, ETC. i) Many plants can be kept in captivity t. Btanical gardens and arbretums are the main type f lcatin, but lts f plants are grwn in gardens, in private cllectins, etc. We even have sme critically endangered species (<100 individuals in the wild) grwing right here n campus in the EEB greenhuses. Wrldwide abut 80,000 plant species are grwn in btanical gardens. This is abut 30% f the wrld s plants. Kew Gardens (just utside Lndn) alne has abut 25,000 species, abut 10% f which are glbally threatened. i Often it is easier t maintain plants away frm their natural settings than it is fr animals. This is because they d nt g anywhere, they d nt need much space (usually), and they ften require fairly similar grwing cnditins (dirt). Mst plants als lack the cmplex behavirs that many animals have, making it much easier t keep them alive and breeding. D) SEED BANKS i) Just as technlgy is changing the way zs functin, with increasing attentin t crygenics, there are parallel changes in plant cnservatin and breeding. In particular, there is an increasing fcus n develping seed banks places where the seeds (and smetimes als pllen, tissue cultures, etc.) can be stred ver the lng term. Seed banks have existed fr a lng time, but primarily as a repsitry fr string seeds f cmmercially imprtant species. Nw there is a shift t expand their functin, especially fr endangered species. i In seed banks, the seeds are kept in cld, dark cnditins, which slws dwn metablism and prevents the seeds frm germinating. In this state, they can be preserved fr many years (even decades) as a back-up in case species disappear in the wild. iv) Currently at least 10,000-20,000 f the wrld s plants are represented in seed banks. Sme seed banks (e.g., the ne at Kew Gardens in Lndn) have a gal f btaining nt nly a high representatin f the wrld s plants but als gd gegraphic (and therefre genetic) representatin fr each species. v) Because seeds are small and dn t d anything, they take up very little space and require simple maintenance at relatively lw cst. vi) On the ther hand, seeds d nt last frever and s, peridically, seeds have t be germinated t frm plants that can prduce new seeds. Seed banks are als vulnerable t breaks in the pwer supply that keep the refrigeratrs running. Anther disadvantage is that there are sme seeds that simply dn t survive in strage. Just as with zs, seed banks will nt wrk as a repsitry fr all species. 3. Captive breeding in practice A) PROBLEMS i) Captive breeding prgrams are expensive. Fr example, it is estimated that it is fifty times mre expensive t prtect elephants and rhins in zs than in the wild. They are als inefficient. Cnservatin wrk prceeds ne species at a time in a captive setting, and it fails t d anything t prtect functining 3

4 ecsystems. Cnsequently, it is really nly useful as an abslute last resrt and can never realistically be applied t mre than a tiny prprtin f all species n Earth. i Limited capacity. Captive settings (especially zs, arbretums, and ther settings that deal with big rganisms) usually cannt maintain very big ppulatins hence all the prblems assciated with small ppulatins in the wild exist in captive settings. Genetic prblems are especially relevant in captive settings and much f the wrk that has been dne n cnservatin genetics has been dne in cnjunctin with z ppulatins. iv) Ppulatins are cncentrated. Anther prblem als parallels what happens in nature individuals becme cncentrated int a small area. This is akin t having a narrw range and is a prblem fr the same reasns. v) Adaptatin t artificial cnditins. Taking species ut f their natural setting can have serius prblems because species smetimes adapt (i.e., they evlve) t their captive cnditins. This is because there is selectin fr individuals that d well in captivity, but it has the cnsequence that certain characteristics f the species are lst. The characteristics that are selected fr are ften nt thse that will be mst imprtant in the wild (e.g., yu might accidentally select fr individuals that are nt afraid f peple which might create a ppulatin that is especially vulnerable t persecutin r predatin if they are ever released back int the wild). vi) Behavir. Sme individuals als fail t learn key behavirs needed t survive in the wild. Or learn behavirs that are harmful in the wild. Again these can be huge prblems if captive breeding is being dne with the idea that individuals will be released back int nature. E.g., this has been a cncern in the cndr release prgram where several released cndrs have learned t hang ut arund peple, beg fr fd, etc. Several f these nuisance birds have had t be brught back int captivity; thers have died as a result f their interactins with peple. v Lgistic cncerns. Finally, there are lgistic prblems. Captive breeding prgrams require a lng-term cmmitment because yu cannt simply decide that yu want t stp ding them fr a few years nce they are in prgress (e.g., when the ecnmy turns bad). Als, when breeding is successful there can be s much prductin that facilities cannt cpe with the number f animals. If there are n release prgrams t use the excess individuals there are ethical issues abut what shuld be dne with them. B) DOES IT WORK? i) Ultimately, the biggest questin is: Des ex situ cnservatin wrk? In sme cases the answer is clearly yes. Althugh there are ther cases when things d nt g s well. The Mauritius kestrel prvides an example f hw ex situ cnservatin and captive breeding can save a species frm extinctin. These small falcns were dwn t nly 4 individuals in 1974 (due t habitat lsses and the effects f pesticides such as DDT). A captive breeding prgram was initiated with birds being bred in Britain and the US. By 1996, the ppulatin had increased s that there were abut 100 breeding pairs in the wild and a ttal ppulatin f abut 400. In 2000, the IUCN decided that the species was ding well enugh that it did nt need t be classified as Endangered any mre (thugh it is still cnsidered Vulnerable because the ppulatin is still small and restricted t a tiny range). 4

5 4. Release prgrams A) THREE TYPES OF RELEASE i) Reintrductins. These invlve the release f individuals int an area frm which the species has been extirpated. The release f gray wlves int i Yellwstne is an example f an extremely successful reintrductin. Augmentatin. Smetimes a species persists in the wild, but is precariusly clse t ging extinct. In these situatins, captive-bred individuals might be released int the ppulatin t increase the ppulatin size r t increase genetic diversity in the ppulatin. Examples include the whping crane release prgram. Intrductin prgram. In sme cases it is nt pssible t release individuals int their native range, r it is desirable t mve individuals away frm their native range t a new site (this is called translcatin). An example f this is the Devil s hle pupfish. Can yu think f reasns why this might be desirable? B) WHAT MAKES A RELEASE PROGRAM WORK? i) Remval f the threat. Seems pretty bvius, but ften this is hard t d. If yu d nt remve the threat thugh, the chances f success are limited. Sft release. Varius things can be dne t make it easier fr released individuals t survive, especially in the perid immediately after release. These include: prviding supplemental fd, prviding shelter where animals can rest, putting up pre-release cages fr the animals t live in fr a perid prir t release, timing the release t ccur at a time f year when cnditins are gd, ensuring that sme f the released individuals have experience living in the wild, prviding behaviral training (e.g., t be afraid f predatrs) fr individuals prir t their release, etc., etc. i Ppulatin size. Release prgrams are mre likely t be successful if a large number f individuals (>100) are released, r if additinal individuals are peridically added t the ppulatin. Releases at multiple sites als increase the lng term persistence f the ppulatin. Hw des this relate t the infrmatin I gave n invasive species? iv) Crrect genetic stck. Ensuring that released individuals are as genetically similar as pssible t the histric ppulatin is imprtant. These individuals are generally mst likely t have apprpriate adaptatins fr the envirnment int which the release ccurs. v) Release in cre f riginal range. Studies have shwn that release prgrams are mre successful when they release individuals int the cre f the species histric range than when the release ccurs near the periphery f the histric range. Why d yu think this is? vi) Pst-release mnitring. Mnitring the ppulatin after the release is imprtant, nt just because it tells yu whether the release wrked, but als because it can guide yu as t whether yu need t release mre individuals (e.g., t help the ppulatin vercme stchastic events such as inbreeding r sex rati imbalance), r alternatively whether yu shuld nt release any mre (e.g., if the threat is still present and all released individuals just die). v Public educatin. Release prgrams are expensive and cnsequently need t be well justified thrugh effective public educatin prgrams. In sme cases the educatin is critically imprtant if the prgram is t exceed. Fr example when pink pigens were first released back int Mauritius many f the released birds were killed fr fd. N ne knew what they were, r that there was a gd reasn fr leaving them alne. 5

ANXIETY SYMPTOMS INTERVENTION SESSION HANDOUTS. Introduction to Fighting Fear by Facing Fear. Making a Fears and Worries List

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