UWSS Research

Do you remember seeing some of the deer in Oak Bay wearing some radio collars like this one? That was the first part of a two-part study on the population of deer in Oak Bay. The first part of the project was focused on giving an accurate measure of the population of urban deer in Oak Bay. This includes analyzing the movement of deer – do they have large home ranges? Do they wander or are they staying in a relatively small area?

We’re currently in the second phase of this study, assessing the effectiveness of using an immunocontraceptive (IC) vaccine as a non-lethal method of population control. We’ve also swapped out those radio collars and instead we use simple coloured collars with tags to help us keep track of which does were treated with IC. All the deer we have handled have ear tags to help us identify them.

This study is funded by the Province of British Columbia, the Municipality of Oak Bay, and donations from our supporters. Our methods have undergone rigorous review and meet regulations put in place by the Canadian Council on Animal Care and BC Fish and Wildlife. Our project is also endorsed by the BC SPCA.

Have you seen a deer with a collar? We have some FAQs about the collars that you might like to read.

2021 Oaky Bay results
Oak Bay Deer Project

The results are in once more! Expanding on the 2019 findings of where deer can be found in Oak Bay, we were able to identify that deer are honing in on areas with lush green vegetation and large-sized residential lots (as well as parks, green spaces, and golf courses). Results indicate that the conversion of the historic drought-resistant Garry oak ecosystems into the lush, landscaped urban environment of Oak Bay is likely supporting an urban Columbian black-tailed deer population than the native Garry oak ecosystem would.

Additionally, after just one year of immunocontraception (IC: in the fall of 2019), the relative abundance of fawns decreased by nearly 60% in 2020. The adult deer population stayed largely constant over the first year of IC (approx. 100 deer in all of Oak Bay), but the decrease in the abundance of fawns should result in a decrease in adult deer as fewer fawns will be maturing into adulthood. Hopefully, we’ll be able to start seeing this in the upcoming years.

If you’d like to read either the 2019 or 2021 Preliminary Reports that were submitted to the District of Oak Bay and the Province you can access them here: 

UWSS 2019 Progress Report

UWSS 2021 Interim Report on habitat use

UWSS 2021 Interim Report on fawning rates after immunocontraception

Esquimalt Deer Project

The 2019 Report is the second year of a 3 year monitoring project in Esquimalt. The methods used in Esquimalt aren’t as precise as the ones used within Oak Bay, but still allows a baseline monitoring of the deer population within the Township. Interestingly, there was no increase in the number of deer between this year and last year, indicating that deer population numbers are quite stable.

Esquimalt is awaiting results of the immunocontraception program in nighbouring Oak Bay and hopes to target its management efforts to best effect.

Would you like to read more on the Second Annual Report that was submitted to the Township of Esquimalt and the Province in February 2019? You can access the full report here: Esquimalt Deer Survey 2018 Report!