Cats and Birds

by Gray Merriam

A recent study by Environment Canada published in Avian Conservation and Ecology estimated that cats kill between 105 million and 308 million birds in a year (mid-point of 204 million). Pet cats accounted for about 38 percent of the total. Homeless or feral cats killed the rest. Cat predation is considered important in Canada in ten bird species that are at risk.

Loss, Will and Marra published estimates of cat predation on birds in the USA. (Nature Communications 4, No. 1396, 2013) They estimated that free-ranging domestic cats kill 1.3 to 4.0 billion birds annually (plus 6.3 to 22.3 billion mammals). Unowned cats, as opposed to owned pets, cause the majority of this mortality. Their "rigorous data-driven" estimate of bird mortality by cats exceeds any previous estimate and also exceeds all estimates of collisions with windows, buildings, communication towers, vehicles and pesticide poisoning.

Keeping cats from roaming, day and night, could lower numbers of bird deaths and help save some species.

Keeping cats from roaming– keeping them in the house or in a kennel, just like dogs, could save more than just the birds. Preventing cats from roaming, particularly at night could prevent the deaths of the cats by predation. Food habits studies of coyotes show clearly that coyotes prefer cat two to one over any other food. Food habits studies of fishers show that cats seldom appear in their diet. It’s coyotes that get them – and cars.

Cat owners commonly argue that it’s natural for cats to catch birds and therefore it’s fine to let them roam. Not so. The huge numbers of cats brought into nature by humans is unnatural. Domestic cats are too numerous and are supported by our affection so even if they are short of prey, we take them in and feed and cuddle them. If you believe hunting by cats is normal, leave them outside all the time and don’t feed them and let the coyotes do the management. Otherwise, don’t let them roam and become another contributor to the loss of bird species.

Gray Merriam