On cats killing birds

An article in Global Ecology and Conservation (Vol. 3, 2015, pp. 359-366) offers a solution to the massive killing of birds by free-roaming cats:

Birds be safe: Can a novel cat collar reduce avian mortality by domestic cats (Felis catus)?” (1.15 MB), by S.K. Willson, I.A. Okunlola, and J.A. Novak

In August 2015 it was reported to be one of the five top downloaded articles from this journal.


The domestic cat (Felis catus) has been described as the largest anthropogenic threat to songbird populations in North America. We examined the effectiveness of a novel cat collar in reducing avian and small mammal mortality by cats. The 2-inch wide Birdsbesafe(R) collar cover (CC) is worn over a nylon quick-release collar, and the bright colors and patterns of the CC are hypothesized to warn birds of approaching cats. We conducted two seasonal trials, each lasting 12 weeks, in autumn 2013 (n = 54 cats) and spring 2014 (n = 19 cats). Cats were randomly assigned to two groups, and CCs with interior collars were removed or put on every two weeks, to control for weather fluctuations and seasonal change. Cats wearing Birdsbesafe(R) CCs killed 19 times fewer birds than uncollared cats in the spring trial, and 3.4 times fewer birds in the fall. Birdsbesafe(R) CCs were extremely effective at reducing predation on birds. Small mammal data were less clear, but did decrease predation by half in the fall. The Birdsbesafe(R) CC is a highly effective device for decreasing bird predation, especially in the spring season. We suggest that the CCs be used as a conservation tool for owned as well as feral cats.


more on cats killing birds

Note: In our <comments on Ottawa’s draft Wildlife Strategy (24 May 2013)>, we said:

Missing from the Strategy is guidance on the conflict between cats and wildlife. A recent article in Nature Communications (Loss et al., 29 Jan 2013) documented the truly massive impact of free-roaming domestic, barn and feral cats on mortality of birds in particular. There are ways of mitigating each type of conflict and these should be part of the City’s strategy.

The article by Loss et al. is here.


Bird killings: Governments not taking action

Albert Koehl, Adjunct professor of natural resources management at Osgoode Hall Law School, York University, wrote an op-ed in the Globe & Mail of September 18, 2015, wherein he advises cat owners to control their pets and avoid mass killings of birds.

He also notes that, in the fall of 2010, the federal government abruptly abandoned a regulatory initiative that would have protected migratory birds from large-scale industrial threats.  The initiative had been provoked by a finding of the Commission for Environmental Cooperation (part of NAFTA) that Environment Canada was failing to enforce the Migratory Birds Convention Act against companies engaged in clear-cut logging.

Similarly, he notes that a 2013 court ruling clarified that Ontario has the power to regulate commercial building owners responsible for large numbers of bird deaths from daytime window strikes.  But again, the Province has not shown any inclination to act.

FLAP (now Safe Wings Ottawa) may change that!

E.D. – 6 October 2015


Volume 130 No. 2 (2016) of the Canadian Field-Naturalist has a book review by Randy Lauff of

Free-ranging Cats – Behavior, Ecology, Management, by Stephen Spotte. 2014. John Wiley and Sons, Ltd., Southern Gate, Chichester, West Sussex, UK, PO19 8SQ. 320 pages, 123.95 CAD, Cloth.

From Science Alert, 12 february 2021, by Jacinta Bowler:
“Scientists Find a Simple Way to Make Your Cat Hunt Less Wildlife – Change Its Diet”

Based on research published in Current Biology, February 11, 2021

(Four authors. DOI: https://doi.org/10.1016/j.cub.2020.12.044)


Predation by domestic cats can be a threat to biodiversity and is a social problem

Providing high-meat-protein food and object play both reduce predation by cats

Rather than impeding hunting, these non-invasive measures reduce tendency to hunt

Cat owners might engage more with measures that benefit cats as well as wildlife.