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Bio­di­ver­sity


A Col­lec­tion of News by Moos


201726Nov18:20

For­est frag­men­ta­tion leads to win­ners and losers – those liv­ing on the edge win

Infor­ma­tion
pub­lished 26 Novem­ber 2017 | mod­i­fied 26 Novem­ber 2017
Archived

Sunda pangolin borneoBreak­ing up the rain­for­est into small, iso­lated patches is forc­ing more species to live at the for­est edge and putting those that are depen­dent on the for­est core at risk.

Research pub­lished online on 1 Novem­ber in the sci­en­tific jour­nal Nature high­lights how bio­di­ver­sity is chang­ing as a result of defor­esta­tion – forc­ing some species to the brink of extinc­tion while oth­ers flour­ish in the chang­ing environment.

Col­lect­ing data for over 1,500 for­est ver­te­brates, the research team led by New­cas­tle Uni­ver­sity, UK, and Impe­r­ial Col­lege Lon­don, found that 85% of species are now being impacted by this for­est fragmentation.

The win­ners are those that seek out the for­est edge while the losers are those that rely on the for­est core and whose habi­tat is being con­stantly squeezed.

Inform­ing con­ser­va­tion
Devel­op­ing a sys­tem to pre­dict which species are likely to dis­ap­pear first from our chang­ing for­est habi­tats, the team is now hop­ing to use this infor­ma­tion to inform for­est con­ser­va­tion and restora­tion efforts.

Trop­i­cal forests, and the ani­mals they har­bour, are being lost at alarm­ing rates but in order to pro­tect them we need to know exactly how frag­men­ta­tion of the land is impact­ing on the ani­mals that live there.

Dr Mar­ion Pfeifer, lead author, School of Biol­ogy, New­cas­tle Uni­ver­sity, UK.

This is crit­i­cal for the hun­dreds of species that we iden­ti­fied as being clearly depen­dent on intact for­est core areas – that is for­est which is at least 200-​400m from the edge. These include species such as the Sunda pan­golin (Manis javan­ica), the Bahia Tapac­ulo (Eleoscy­talo­pus psy­chopom­pus), the Long-​billed Black Cock­a­too (Zanda bau­dinii) and Baird’s tapir (Tapirus bairdii),” Pfeifer adds.

Long-billed black cockatooA female Long-​billed Black Cock­a­too (Calyp­torhynchus baudinii),also called Baudin’s Black Cock­a­too, at Mar­garet River, West­ern Aus­tralia.
Image credit: Ricko1 — Wikipedia, licensed under the Cre­ative Com­mons Attri­bu­tion 2.0 Generic license.

These species were highly sen­si­tive to the chang­ing habi­tat and there­fore more likely to dis­ap­pear in land­scapes that encom­pass only a small pro­por­tion of intact forest.”

Win­ners and losers — 85% of species affected
Half the world’s for­est habi­tat is now within 500m of a ‘for­est edge’ due to the expan­sion of road net­works, log­ging, agri­cul­ture and other human activ­ity. These edges look dif­fer­ent to the rest of the for­est: with more light, less mois­ture and gen­er­ally higher temperatures.

Using species’ abun­dance data col­lected from frag­mented land­scapes world­wide, the team analysed 1,673 species of mam­mals, birds, rep­tiles and amphib­ians to see how they respond to edges. Using new spa­tial and sta­tis­ti­cal analy­ses devel­oped at Impe­r­ial Col­lege Lon­don, they were able to show that 85% of species’ abun­dances are affected, either pos­i­tively or neg­a­tively, by for­est edges.

More impor­tantly, edge effects cre­ate species com­mu­ni­ties near edges that bear lit­tle resem­blance to the com­mu­ni­ties of for­est inte­ri­ors, and this species turnover likely reflects dra­matic changes to the eco­log­i­cal func­tion­ing of mod­i­fied for­est habitats.

About half of species win from the for­est change; they like the edges and so avoid the deep for­est, pre­fer­ring instead to live near for­est edges,” Robert Ewers, Pro­fes­sor of Ecol­ogy at Impe­r­ial Col­lege Lon­don, explains. “The other half lose; they don’t like the edges and instead hide away in the deep for­est. The win­ners and losers aren’t equal though. Some of the species that like edges are inva­sive like the boa con­stric­tor, while the ones hud­dled into the deep for­est are more likely to be threat­ened with extinc­tion – like the Sunda pangolin.”

Our analy­sis allows us to track species’ abun­dances in response to edge effects to pre­dict the impact on bio­di­ver­sity caused by for­est loss and frag­men­ta­tion,” adds Dr Pfeifer.

This is use­ful for land man­age­ment and as a tool to help guide our con­ser­va­tion efforts. The next step is to use this data and our soft­ware to allow man­agers to cre­ate ‘opti­mal land­scapes’ that com­bine for­est use with bio­di­ver­sity conservation.”

(Source: New­cas­tle Uni­ver­sity news release, 01.11.2017)


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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