"Long before it's in the papers"
January 27, 2015


Domestic cats seen as major killers of wildlife

Jan. 29, 2013
Courtesy of Nature
and World Science staff

As cute and cuddly as they may look, do­mes­tic cats are al­so dead­li­er to their fellow ani­mals than widely real­ized, a new study in­di­cates.

Free-ranging do­mes­tic cats in the Un­ited States kill an es­ti­mat­ed 1.4 bil­lion to 3.7 bil­lion birds eve­ry year, ac­cord­ing to the re­port. That’s much high­er than pre­vi­ous es­ti­mates of about one bil­lion.

The fuzzy fe­li­nes—pets or de­scen­dants of pets—al­so kill 6.9 bil­lion to 20.7 bil­lion mam­mals eve­ry year­ly, adds the re­port, which was based on a re­view of lo­cal stud­ies com­bined with some sta­tis­ti­cal as­sump­tions.

All told, re­search­ers said, the es­ti­mat­ed death toll makes the com­mon kit­ty, the spe­cies Fe­lis ca­tus, the No. 1 cause of death—among causes ul­ti­mately at­trib­ut­a­ble to hu­mans—for wild U.S. birds and mam­mals.

The re­search­ers found that cats with­out hu­man own­ers ac­count for the ma­jor­ity of the killings: an es­ti­mat­ed 69 per­cent and 89 per­cent for birds and mam­mals, re­spec­tive­ly.

“Sci­en­tific­ally sound con­serva­t­ion and pol­i­cy in­ter­ven­tion is needed to re­duce this im­pact” on wild­life, wrote the re­search­ers, Scott R. Loss of the Smith­so­nian Con­serva­t­ion Bi­ol­o­gy In­sti­tute in Wash­ing­ton, D.C., and col­leagues. “This mag­ni­tude of mor­tal­ity is far great­er than pre­vi­ous es­ti­mates of cat preda­t­ion on wild­life.”

The findings appear in the Jan. 29 advance online is­sue of the jour­nal Na­ture Com­muni­ca­tions.

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As cute and cuddly as they may look, domestic cats are also deadlier than widely realized, a new study indicates. Free-ranging domestic cats in the United States kill an estimated 1.4 billion to 3.7 billion birds every year, according to the report. That’s much higher than previous estimates of about one billion. The fuzzy felines—pets or descendants of pets—also kill 6.9 billion to 20.7 billion mammals every yearly, adds the report, which was based on a review of local studies combined with some statistical assumptions. All told, researchers said, the estimated death toll makes the common kitty, the species Felis catus, the No. 1 cause of death—among the causes ultimately attributable to humans—for wild U.S. birds and mammals. The researchers found that cats without human owners account for the majority of the killings: an estimated 69 percent and 89 percent for birds mammals, respectively. “Scientifically sound conservation and policy intervention is needed to reduce this impact” on wildlife, wrote the researchers, Scott R. Loss of the Smithsonian Conservation Biology Institute in Washington, D.C., and colleagues. “This magnitude of mortality is far greater than previous estimates of cat predation on wildlife.”