Tag Archives: Threats to Biodiversity

On Cats and Birds and Policy Gaps

1 Reply

Many people in western societies like to keep cats as pets, and with that simple observation we run into two problems that require resolution. First, cats are killers of wildlife, particularly birds but also an array of other small prey. Most people do not believe this, because cats are adored and make good, if somewhat disinterested pets. So, my first point might be that if you think cats are not killers, I invite you to keep another cat like a mountain lion for a pet. But we need some data on the kill rate of cats. Before we begin this search, we should note that cats can be kept inside dwellings or in cat runs with no access to birds or other prey. If this is the case, no problem exists for wildlife, and you can skip to the bottom of this blog for one other issue to recognize.

How much mortality can be traced to cats roaming out of doors? This will include normal house cats let out to roam at night, as well as wild cats that have been discarded by their owners into the wild. There is extensive literature on cats killing birds. If you want a brief introduction Greenwall et al. (2019) discuss a nesting colony of Fairy Terns, a threatened species of Australian seabird, along a beach in southwestern Australia. With detailed observations and photographic data, they recorded the complete failure of all 111 nests in this colony with the loss of all tern chicks in the early summer of 2018. The predator was a single desexed feral cat. Many local governments allow the capture of feral cats with the protocol that they are desexed and then released back into the environment. Clearly desexing and release does not remove the problem.

The domestic cat has been spread world-wide, so that the cat problem is not a local one. Li et al. (2021) completed a survey of feral cat kill rates in the eastern part of China and found that the minimum annual loss of wildlife to feral cats was in the range of 2.7-5.5 billion birds, and 3.6-9.8 billion mammals, as well as large numbers of amphibians, reptiles, and fish. In gardens in Western Europe cat predation on ringed birds studied with precise data showed that up to 25% of dead birds were killed by cats, but these data varied greatly among species (Pavisse et al. 2019). For the European Robin which often feeds on the ground 40% of all ringed birds were killed by cats, for the European Greenfinch the figure was 56% of ringed birds killed. These are just two examples of an extensive literature on cat kills going back many years (Calvert et al. 2013).

What can we do about this predation? As with too many conservation issues the answer is simple but difficult to implement: Ban all cats from free-ranging unless they are on a leash and under control. Keep cats in the house or in special cat runs that are confined outdoors. Ban completely stupid programs of catching feral cats, sterilizing them, and releasing them back to the wild to continue their killing. Cats may make marvellous pets but need to be kept indoors. Many people would support these measures but many cat owners would disagree about such measures. Some progress is being made in urban environments in which some suburbs do not permit cats to roam freely.

Feral cats are a serious issue in Australia because they attack many threatened birds and reptiles (Doherty et al. 2019). In this case a federal environmental policy to kill 2 million cats is popular but from a conservation viewpoint still a poor policy. We do not know if killing 2 million cats is too much or too few, and without specific goals for conservation and careful monitoring of bird populations widespread killing my not achieve the goal of protection for threatened species. Eradications of cats on islands is often feasible, but no mainland eradication is currently possible.

As conservation biologists know too well, when humans are the problem, wise policies may not be implemented. So, the second issue and the bottom line might be to consider the human costs of cat ownership. Adhikari et al. (2020) report a highly significant association between the risk of dying from colon cancer and cat ownership. These results are not confounded by sedentary lifestyle, cigarette smoking or socio-economic status. In a similar study Adhikari et al. (2019) found that living with a cat significantly increased the death rate from lung cancer among women. The cause of these associations cannot yet be deciphered but are postulated to result from mycotoxins, toxic secondary metabolites produced by fungi (moulds) in cereal crops used in cat food. Aflatoxin is a mycotoxin that produces well-known chemicals that are seriously toxic to animals and humans.

These kinds of studies of associations arising from surveys can be tossed off by the typical comments ‘these-things-do-not-concern-my cats’ or ‘that there is no proof of the exact cause’ so if you are concerned you might investigate the literature on both mycotoxins and the diseases that cats carry.

It is up to humans to solve human problems, but up to conservation biologists to point out the detrimental effects of household pets and their feral cousins on wildlife. The present situation is a complete policy failure by governments at all levels. Good science is relatively easy, good policy is very difficult.

Adhikari, Atin, Adhikari, A., Jacob, N. K., and Zhang, J. (2019). Pet ownership and the risk of dying from lung cancer, findings from an 18 year follow-up of a US national cohort. Environmental Research 173, 379-386. doi: 10.1016/j.envres.2019.01.037.

Adhikari, Atin, Adhikari, A., Wei, Y. D., and Zhang, J. (2020). Association between pet ownership and the risk of dying from colorectal cancer: an 18-year follow-up of a national cohort. Journal of Public Health 28, 555-562. doi: 10.1007/s10389-019-01069-1.

Calvert, A.M., Bishop, C.A., Elliot, R.D., Krebs, E.A., Kydd, T.M., Machtans, C.S., Robertson, G.J., 2013. A synthesis of human-related avian mortality in Canada. Avian Conservation and Ecology 8: 11. doi 10.5751/ACE-00581-080211.

Doherty, T.S., Driscoll, D.A., Nimmo, D.G., Ritchie, E.G., and Spencer, R. (2019). Conservation or politics? Australia’s target to kill 2 million cats. Conservation Letters 12, e12633. doi: 10.1111/conl.12633.

Li, Yuhang, Wan, Yue, Shen, Hua, Loss, S.R., Marra, P.P., and Li, Zhongqiu (2021). Estimates of wildlife killed by free-ranging cats in China. Biological Conservation 253, 108929. doi: 10.1016/j.biocon.2020.108929.

Greenwell, C.N., Calver, M.C., and Loneragan, N.R. (2019). Cat Gets Its Tern: A Case Study of Predation on a Threatened Coastal Seabird. Animals 9, 445. doi: 10.3390/ani9070445.

Pavisse, R., Vangeluwe, D., and Clergeau, P. (2019). Domestic Cat Predation on Garden Birds: An Analysis from European Ringing Programmes. Ardea 107, 103-109. doi: 10.5253/arde.v107i1.a6.

Bill 24 – A threat to biodiversity and ecosystems associated with agriculture in BC

Leave a reply

Bill 24 – a threat to biodiversity and ecosystems associated with agriculture in BC

buse 2010Agriculture has often been viewed as a threat to natural environments. This is clearly the case when forests are cut down to create pastures for grazing animals or fields for high value crops.  However, in a world already greatly manipulated by human activities, agricultural areas have increased in significance as refuges for organisms ranging from wildlife, birds, insects, plants, and soil microbes.  In addition agricultural lands can preserve wetlands, riparian habitats, streams, wind breaks and patches of forest.  These habitats and the organisms that dwell there benefit the agricultural industry and society in general by providing healthy, functioning ecosystems both on and adjacent to agriculture.

In British Columbia Canada, agricultural lands have been protected to some degree since 1973 by the Agricultural Land Reserve administered by the Agricultural Land Commission. Approximately 47,000 sq. km have been preserved for agricultural use either now or in the future. It has been a continual battle over the years to prevent lands from being removed from the land reserve and large tracts have been used in land claim settlements with First Nations and for a variety of development projects.  For the latter, the claim has been made that the land under contention is not sufficiently high quality for agriculture or the need for economic development is greater than the need for food security

A new threat to the ALR is currently before the BC Legislature, Bill 24.  The proposed act will make it easier for many non-agricultural uses to be developed on agricultural lands. It will seriously change the operation of the Agricultural Land Commission, and will allow changes in the classification of Agricultural lands to occur without a transparent, public process based on sound, scientifically derived information. This bill is deeply flawed and threatens the sustainability and security of agricultural production. It puts the survival of many species and ecosystems at risk. It is particularly ill timed as the future of agriculture will be greatly changed as the climate continues to warm and northern areas become more suitable for crops.

A number of ecologists have voiced their concerns about the impact of this proposed bill in a letter to Primer Christy Clark.  Their concerns are not only about the impacts on the sustainability of the agricultural industry, but also about the enormous threats to biodiversity, species at risk and the functioning ecosystems in British Columbia that would follow the reduction of the Agricultural Land Reserve. This letter is copied below.

From: The undersigned concerned scientist and naturalists

To: Premier Christy Clark

PO BOX 9041
STN PROV GOVT
VICTORIA, BC
V8W 9E1

Dear Premier Clark,

The British Columbia Government’s recently proposed changes to the Agriculture Land Commission (the Commission) Act greatly concerns many scientists for three reasons.

First, the revised changes to the governance and decision-making structure of the Commission reduces the ability for science to inform land use decisions. Second, the shift to divide the decision-making process regarding land classification into southern and interior zones will increase pressure to remove land from the reserve at a cost to the general good. And finally, the rationale for the division of the province into two jurisdictions, based simply on the value of the crops, overlooks the importance of other values associated with agricultural lands such as habitat for wildlife, endangered species, and contributions to ecosystem services.

Agricultural lands that occur in all regions of the province hold many values other than simply crop production. These areas contain wetlands, streams, ponds, riparian areas, woodlands, hedgerows, and uncultivated grasslands that are either adjacent to or integral to farm operations. These areas are instrumental in protecting functioning healthy ecosystems and in many cases, these diverse services help boost agricultural production. Many of the ecosystems encompassed by the Agricultural Land Reserve are rare in British Columbia and they provide habitat for a number of the Province’s most threatened or endangered species such as the burrowing owl, American badger, yellow-breasted chat, sage thrasher, Nooksack dace, and west slope cutthroat trout.  Other more common species that occur on Agricultural Land Reserve land are integral to agricultural production. These species range from soil microbes that sequester carbon below pasturelands, to birds such as the western meadowlarks, swallows, and common nighthawks whose populations are already declining. Species prized for hunting such as deer and elk also use so called marginal agricultural lands.  These species decline when agricultural lands are removed from production, marginal lands are converted to more intensive uses, or nonagricultural developments are permitted on agricultural lands. Allowing more nonagricultural uses on ALR land and the release of more lands from reserves will have the unintended consequence of threatening many important ecosystems and, by extension, many valuable species including species-at-risk.

Changing the current structure of the Commission to one that does not incorporate scientifically-derived information is deeply-flawed. Additionally, making changes to such an important piece of provincial legislation without consultation with the public, the agricultural industry, or scientists in general prevents relevant information and viewpoints to factor into informed decision-making. Allowing the agricultural industry to move forward with alternatives that incorporate science-based decision making within the current legislative framework are valid alternatives to altering the current reserve framework. These and other options should be explored because failing to incorporate alternate view points and scientifically derived information into the Commissions’ decision-making framework threatens the health of British Columbia’s ecosystems and endangers its biodiversity. The lack of a process to access and incorporate science-based information into the proposed framework threatens the biodiversity of British Columbia’s ecosystems and the sustainability and security of agricultural production in a changing climate.

We call upon the government of British Columbia to include scientifically derived information in the evaluation of the impacts of changes to Agricultural Land Reserve that may impact the health of British Columbia’s ecosystems and species at risk.

Sincerely,

The undersigned concerned scientists and naturalists

Authors

William Harrower RP Bio, PhD Candidate UBC

Judith Myers Professor Emeritus UBC

Sarah Otto, Fellow Royal Society of Canada, Director of Biodiversity Research Centre, Professor, UBC

Eric Taylor, Director Beaty Biodiversity Museum, Professor UBCElizabeth Kleynhans PhD Candidate UBC

 

 

Signatories

 

Angert Amy, Canada Research Chair in Conservation Ecology, Assistant Professor, University of British Columbia
Arcese Peter, FRBC Chair in Applied Conservation Ecology, Professor, University of British Columbia
Baker Sandra, Senior Environmental Assessment Specialist, RP Bio, n/a
Baute Gregory J. , PhD Candidate, University of British Columbia
Bears Heather, Wildlife Ecologist, PhD, Zoetica Wildlife Research Services
Bestbier Regina, Research Assistant, University of British Columbia
Beyers Rene, Associate Researcher, University of British Columbia
Bomke Art, Professor Emeritus, University of British Columbia
Bradfield Gary, Associate Professor, University of British Columbia
Brotz Lucas, PhD Student, University of British Columbia
Bunnell Fred, Professor Emeritus, University of British Columbia
Burton Philip J., NW Regional Chair, Associate Professor, UNBC
Burton Carla, Phd, Symbios Research and Restoration
Byers Sheila, Registered Professional Biologist, Beaty Biodiversity Museum
Cannings Richard, Senior Programs Biologist, Bird Studies Canada
Carefoot Tomas, Professor Emeritus, University of British Columbia
Christensen Villy, Professor, University of British Columbia
Clark Trisha, Research Technician, University of British Columbia
Cockle Kristina, NSERC Post-doctoral Fellow, Louisiana State University
Cooke James, Lecturer, University of British Columbia
Couch Brett, Instructor, University of British Columbia
Cumming Preston, Post-Doctoral Fellow, University of British Columbia
Davis Helen, Senior Wildlife Biologist, Artemis Wildlife Consultants
Doebeli Michael, Fellow of American Association for the Advancement of Science, Professor, University of British Columbia
Durand Ryan, Senior Ecologist, RP Bio. , Durand Ecological Ltd.
Dykstra Pamela, Master of Resource Management, RP Bio, PR Dykstra & Associates Resource Management Ltd.
Enns Katherine, MSc RP Bio., Delphinium Holdings Inc. (formerly Larkspur Biological Consultants Ltd.)
Fenneman James D., PhD Candidate, University of British Columbia
Fraser Lauchlan, Professor, Thompson Rivers University
Frid Leonardo, Systems Ecologist, Apex Resource Management Solutions Ltd.
Gibeau Pascale, RP Bio. PhD Student, Simon Fraser University
Gillis Elizabeth, Professor, Vancouver Island University
Gosselin Louis, Associate Professor, Thompson Rivers University
Hackinen Alisha, MSc Student, University of British Columbia
Halsey T. Gordon
Harrison Bruce, Registered Professional Biologist, Independent Practicing Biologist
Hauert Christoph , Associate Professor, University of British Columbia
Hehenberger Elisabeth, Post-Doctoral Fellow, University of British Columbia
Henry Greg, Professor, University of British Columbia
Hill Ryan, Professional Biologist, Azimuth Consulting Group Partnership
Hodges Karen, Associate Professor, University of British Columbia
Hoffos A Robin, Naturalist, Citizen
Houde Isabelle, MSc. RP Bio, Association of Professional Biology
Irwin Darren, Associate Professor, University of British Columbia
Javney Mohr Carmelle, Junior Fellow, The Chester Ronning Centre for the Study of Religion & Public Life
Jose Mereno Geraldes Armando, Research Associate, University of British Columbia
Kaytor Benita, MSc student, UNBC
Kerry Mara, Director of Science and Policy, David Suzuki Foundation
Koot Cathy, Research Coordinator, RP Bio, University of British Columbia
Krzic Maja, Professor, University of British Columbia
Ladell Jason, Registered Professional Biologist, Independent Practicing Biologist
Larsen Karl, Professor, Thompson Rivers University
Latimer Susan, Registered Professional Biologist, Independent Practicing Biologist
Lawson Julia, MSc student, University of British Columbia
Le Renard Ludovic, PhD Candidate, University of British Columbia
Leathem Jamie, MSc student, University of British Columbia
Leduc-Robert Genevieve, MSc student, University of British Columbia
Leering Gerry, Registered Professional Biologist, past President, Association of Professional Biology
Lehmann Crysta, n/a, University of British Columbia
Leskiw Leonardo, Senior Soil Scientist, Paragon Soil and Environmental Consulting
Letaw Alathea, PhD Candidate, University of British Columbia
Lewis Alan, Professor Emeritus, University of British Columbia
Lin Sherry, University of British Columbia
Lion Christine, Environmental Scientist, Stantec
Lussier Jason, University of British Columbia
Machmer Marlene M., Registered Professional Biologist, Pandion Ecological Research Ltd.
Mahon Todd, Wildlife Ecologist, RP Bio, Wildfor Consultants Ltd
Martone Patrick T., Associate Professor, University of British Columbia
Matthewson Lisa, Professor Emeritus, University of British Columbia
McCune Jenny L, Liber Ero Postdoctoral Fellow, University of Guelph
McGrath Kate , student, University of British Columbia
Millen Sandra, Sr. Instructor Emerita, University of British Columbia
Mobach Annmarie, self-employed
Moore Jonathan, Liber Ero Chair of Coastal Science and Management, Assistant Professor, Simon Fraser University
Morien Evan, Bioinformatician, MSc, University of British Columbia
Mosquin Daniel, Research Manager, University of British Columbia
Moyers Brook, PhD Candidate, University of British Columbia
Neill William E., Professor Emeritus, University of British Columbia
Neville John, President, BC Nature (Federation of BC Naturalists)
Osmond Matthew, PhD Candidate, University of British Columbia
Pollock Carol, Director of 1st Year Biology, Professor of Teaching, University of British Columbia
Power Damian, Registered Professional Biologist, Wolfhound Wildlife Services
Rahme Ann, Biologist, Fisheries and Oceans Canada
Reid Anya, PhD Student, University of British Columbia
Rieseberg Loren, Professor, University of British Columbia
Rodgers Thea, student, University of British Columbia
Rogic Sanja, Research Associate, Center for High-Throughput Sequencing
Rudman Seth, PhD Candidate, University of British Columbia
Ruskey Jennifer, MSc student, University of British Columbia
Salomon Anne, Assistant Professor, Simon Fraser University
Samuels Lacey, Botany Department Head, Professor, University of British Columbia
Scholer Micah, PhD Candidate, University of British Columbia
Seghers Ben, Lecturer (retired), Oxford
Shartau Ryan, PhD Candidate, University of British Columbia
Siegle Matthew, PhD Candidate, University of British Columbia
Smith Jackie, Senior Manager, RP Bio. P Ag., SLR Consulting Ltd
Snyder Joan, PhD, RP Bio. , Retired
Soto Marybel, MSc Student, University of British Columbia
Stafl Natalie, MSc Student, University of British Columbia
Starzomski Brain, Assistant Professor, University of Victoria
Steele Fiona, Senior Biologist, Diamond Head Consulting Ltd.
Suarez Adriana, PhD Candidate, University of British Columbia
Sullivan Tomas, Professor, University of British Columbia
Thiel Bryanna, MSc student, University of British Columbia
Thorley Joseph, PhD, RP Bio. , Poisson Consulting
Tonya Ramey, PhD Candidate, University of British Columbia
Turkington Roy, Professor, University of British Columbia
Wang Jessie, student, University of British Columbia
Wellwood Debbie, Wildlife Ecologist, RPBio, Raven Ecological Services
Werring John, Senior Science and Policy Advisor, MSc. RP Bio., David Suzuki Foundation
William Ramey, Professor of Teaching, University of British Columbia
Williams Jennifer, Assistant Professor, University of British Columbia
Worcester Robyn, Conservation Programs Manager, Stanley Park Ecology Society
Xue Xinxin, PhD Candidate, University of British Columbia
Zevit Pamela , Registered Professional Biologist, Adamah Consultants