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Bio­di­ver­sity


A Col­lec­tion of News by Moos


201418Apr22:37

Fenc­ing of wildlife: old-​school! It should be avoided

Infor­ma­tion
pub­lished 18 April 2014 | mod­i­fied 18 April 2014
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Wildlife fences are con­structed for a vari­ety of rea­sons includ­ing to pre­vent the spread of dis­eases, pro­tect wildlife from poach­ers, and to help man­age small pop­u­la­tions of threat­ened species. Human – wildlife con­flict is another com­mon rea­son for build­ing fences: Wildlife can dam­age valu­able live­stock, crops, or infra­struc­ture, some species carry dis­eases of agri­cul­tural con­cern, and a few threaten human lives. At the same time, peo­ple kill wild ani­mals for food, trade, or to defend lives or prop­erty, and human activ­i­ties degrade wildlife habitat.

electric wildlife fenceSo, sep­a­rat­ing peo­ple and wildlife by fenc­ing can appear to be a mutu­ally benefi­cial way to avoid such detri­men­tal effects. But in a paper in the jour­nal Sci­ence, pub­lished on 4 April, sci­en­tists review the ‘pros and cons’ of large scale fenc­ing and argue that fenc­ing should often be a last resort.

Cost of fenc­ing
Although fenc­ing can have con­ser­va­tion ben­e­fits, it also has costs. When areas of con­tigu­ous wildlife habi­tat are con­verted into islands, the result­ing small and iso­lated pop­u­la­tions are prone to extinc­tion, and the result­ing loss of preda­tors and other larger-​bodied species can affect inter­ac­tions between species in ways that cause fur­ther local extinc­tions, a process which has been termed “eco­log­i­cal meltdown”.

In some parts of the world, fenc­ing is part of the cul­ture of wildlife con­ser­va­tion – it’s assumed that all wildlife areas have to be fenced. But fenc­ing pro­foundly alters ecosys­tems, and can cause some species to dis­ap­pear. We’re ask­ing that con­ser­va­tion­ists as well as other sec­toral inter­ests care­fully weigh up the bio­di­ver­sity costs and ben­e­fits of new and exist­ing fences.
(ZSL’s Rosie Woodroffe, lead author of the study)

In addi­tion to their ecosystem-​wide impact, fences do not always achieve their spe­cific aims. Con­struc­tion of fences to reduce human – wildlife con­flict has been suc­cess­ful in some places but the chal­lenges of appro­pri­ate fence design, loca­tion, con­struc­tion, and main­te­nance mean that fences often fail to deliver the antic­i­pated ben­e­fits. Iron­i­cally, in some places, fences also pro­vide poach­ers with a ready sup­ply of wire for mak­ing snares.

Giraffe at a fence in South Africa:

Alter­na­tive meth­ods
Co-​author Simon Hedges of WCS said: “A vari­ety of alter­na­tive approaches – includ­ing bet­ter ani­mal hus­bandry, community-​based crop-​guarding, insur­ance schemes, and wildlife-​sensitive land-​use plan­ning – can be used to mit­i­gate conflicts between peo­ple and wildlife with­out the need for fenc­ing. WCS projects work­ing with local peo­ple and gov­ern­ment agen­cies have shown that human – ele­phant con­flict can be dra­mat­i­cally reduced with­out using fences in coun­tries as dif­fer­ent as Indone­sia and Tanzania.”

Co-​author Sarah Durant of ZSL’s said, “An increased aware­ness of the dam­age caused by fenc­ing is lead­ing to move­ments to remove fences instead of build­ing more. Increas­ingly, fenc­ing is seen as back­wards step in conservation.”

Dis­eases
The desire to sep­a­rate live­stock from wildlife in order to cre­ate zones free from dis­eases such as foot-​and-​mouth has resulted in exten­sive fenc­ing sys­tems, par­tic­u­larly in south­ern Africa. Some of these fences have had dev­as­tat­ing envi­ron­men­tal effects. For­tu­nately, it is increas­ingly recog­nised that a com­bi­na­tion of improved test­ing, vac­ci­na­tion, and stan­dard­ised approaches to meat prepa­ra­tion can pre­vent spread of dis­eases with­out the need to sep­a­rate cat­tle from wildlife by fencing.

The authors con­clude that as cli­mate change increases the impor­tance of facil­i­tat­ing wildlife mobil­ity and main­tain­ing land­scape con­nec­tiv­ity, fence removal may become an impor­tant form of cli­mate change pre­pared­ness, and so fenc­ing of wildlife should be avoided when­ever possible.

How­ever, there are other opin­ions about using fences to sep­a­rate wildlife from humans as a con­ser­va­tion mea­sure. Just over a year ago a report was pub­lished that con­cluded that nearly half of Africa’s wild lion pop­u­la­tions may decline to near extinc­tion over the next 2040 years with­out urgent con­ser­va­tion mea­sures. The plight of many lion pop­u­la­tions is so bleak, the report con­cluded that fenc­ing them in – and fenc­ing humans out – may be the lions’ only hope for survival.



(Source: WCS press release, 03.04.2014; Pan­thera press release, 05.03.2013)

UN Biodiversity decade

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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