Sitat av
TylerDurden4
Uten katter ville det vært rotter overalt
Tull. Rotter veier i gjennomsnitt ti ganger så mye som en mus, som er blant kattens favorittbytter. De færreste huskatter er noe tess som rottefanger og vil i stor grad ignorere rotter som mulig bytte.
Ugler, hauk og rev på den andre siden gjør en utmerket jobb med å holde bestanden nede, noe som er én av grunnene til at disse også har etablert seg i og i nærheten av byer.
Her er et par artikler, for den leselysne:
Cats Are No Match for New York City’s Rats
Cats Are Surprisingly Bad at Killing Rats
Disse er begge basert på intervju med forskerne bak følgende publikasjoner:
Temporal and Space-Use Changes by Rats in Response to Predation by Feral Cats in an Urban Ecosystem
Sitat av Abstract
Feral cats (Felis catus) are predators that cause widespread loss of native wildlife in urban ecosystems. Despite these risks, cats are commonly released as control agents for city rats (Rattus spp.). Cats can influence their prey directly by killing or indirectly through changes to feeding or space-use. However, cats prefer defenseless prey, and there are no data suggesting that cats influence large (>300 g) urban rats.
[...]
Our findings of low levels of predation support why ecologists believe the risks to native wildlife outweighs any benefits of releasing cats. Even though rats were less likely to be seen, they simply shifted their movements and remained present in the system. Our findings that cat presence led to fewer rat sightings may explain the common perception of their value as rat-predators despite the associated risks.
Population impacts of free‐ranging domestic cats on mainland vertebrates
Sitat av Abstract
Domestic cats (Felis catus) have contributed to at least 63 vertebrate extinctions, pose a major hazard to threatened vertebrates worldwide, and transmit multiple zoonotic diseases. On continents and large islands (collectively termed “mainlands”), cats are responsible for very high mortality of vertebrates.
Nevertheless, cat population management is traditionally contentious and usually involves proving that cats reduce prey population sizes.
More than a dozen observational studies, as well as experimental research, provide unequivocal evidence that cats are capable of affecting multiple population‐level processes among mainland vertebrates.
In addition to predation, cats affect vertebrate populations through disease and fear‐related effects, and they reduce population sizes, suppress vertebrate population sizes below their respective carrying capacities, and alter demographic processes such as source–sink dynamics.
Policy discussions should shift from requiring “proof of impact” to a precautionary approach that emphasizes evidence‐driven management to reduce further impacts from outdoor cats.