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Zoos


A Col­lec­tion of News by Moos


201626Mar16:54

Endan­gered ani­mals as well as their par­a­sites should be conserved!

Infor­ma­tion
pub­lished 26 March 2016 | mod­i­fied 26 March 2016
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California condor at San Diego ZooCon­ser­va­tion man­agers who try to keep mem­bers of endan­gered ani­mal species parasite-​free are well-​intentioned but this approach is mis­guided, accord­ing to a new research paper.

In a paper pub­lished online on 24 March in the jour­nal Trends in Ecol­ogy and Evo­lu­tion, Otago’s Pro­fes­sor Hamish Spencer and US evo­lu­tion­ary biol­o­gist Pro­fes­sor Mar­lene Zuk argue that there are good rea­sons why par­a­sites should be con­served along with their endan­gered hosts.

The pair writes that “cap­tive rear­ing pro­grammes, as well as zoos and other facil­i­ties, take for granted that keep­ing their ani­mals healthy and parasite-​free is essen­tial, since by def­i­n­i­tion par­a­sites reduce their host’s fit­ness. But the elim­i­na­tion of a nat­ural com­ple­ment of par­a­sites might have unin­tended consequences”.

Because par­a­sites have been co-​evolving with their hosts for so long, they have become part of the exter­nal envi­ron­ment, and remov­ing par­a­sites, even if it has some pos­i­tive effects on an indi­vid­ual host’s health, has the poten­tial to wreak havoc with eco­log­i­cal systems.”

recent research shows that such expo­sure [to par­a­sites in early life] may enhance the over­all devel­op­ment and effi­cacy of the immune sys­tem in defend­ing against a wide vari­ety of infections
Pro­fes­sor Hamish Spencer, co-​author, Depart­ment of Zool­ogy, Uni­ver­sity of Otago, New Zealand »

Spencer says that for exam­ple, expo­sure to par­a­sites might be cru­cial to the host animal’s devel­op­ment of a fully func­tional immune sys­tem and hence to its survival.

Expo­sure to par­a­sites in early life can con­fer improved resis­tance to the same par­a­sites later on, and recent research shows that such expo­sure may enhance the over­all devel­op­ment and effi­cacy of the immune sys­tem in defend­ing against a wide vari­ety of infections.”

Pro­fes­sors Zuk and Spencer note that zoos and other cap­tive ani­mal facil­i­ties gen­er­ally have exten­sive anti-​parasite pro­ce­dures, and when ani­mals are reared they are not inoc­u­lated with a stan­dard assort­ment of par­a­sitic organisms.

Per­haps more wor­ry­ingly, pro­to­cols of rein­tro­duc­tion pro­grammes often require the very oppo­site, with ani­mals dosed with a range of anti-​parasitic treat­ments before release.”

The researchers assert that “the con­ser­va­tion of par­a­sites might well be an essen­tial part of the con­ser­va­tion of their hosts. Thus, if the goal of con­ser­va­tion is to main­tain bio­di­ver­sity, as well as the eco­log­i­cal and evo­lu­tion­ary processes that gen­er­ate and sus­tain it, then par­a­sites must also be con­served for their host’s sake.”

Pro­fes­sor Spencer says they are not call­ing for con­ser­va­tion man­agers to com­pletely ignore par­a­sites and that major par­a­site infes­ta­tion obvi­ously needs to be treated, but low lev­els of a vari­ety of par­a­site infec­tions might even improve con­ser­va­tion outcomes.


(Source: Uni­ver­sity of Otago news release, 24.03.2016)


Goal: 7000 tigers in the wild

Tiger range countries map

Tiger map” (CC BY 2.5) by Sander­son et al., 2006.

about zoos and their mis­sion regard­ing breed­ing endan­gered species, nature con­ser­va­tion, bio­di­ver­sity and edu­ca­tion, which of course relates to the evo­lu­tion of species.
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