When you think of deer, do you think of a doe feeding in a wilderness meadow, the Disney movie Bambi, or of the light-up decorations that were on display over Christmastime in front yards across Canada? For many people, deer are just that—something far away, a cartoon, or merely an inanimate decoration. However, in some cities in British Columbia, deer are a common, yet divisive, part of the urban landscape.
The native Columbia black-tailed deer (CBTD; a more docile sub-species of the mule deer found on the mainland), has coexisted on the landscape with humans for millennia. The First Nations of southern Vancouver Island used fire for land management that promoted the growth of important food plants like camas and would attract game species like CBTD. However, in the years since European colonization, southern Vancouver Island has grown into 13 municipal districts with a population of over 400,000 people. With the ensuing urban development, suburban sprawl, fire suppression, and predator exclusion has combined to change ecosystem dynamics and species distributions.
Coexistence with humans has resulted in habitat fragmentation, with a whopping 1,807 species at risk of extinction in BC, and over 110 of those species in southern Vancouver Island alone. However, some species do well coexisting with humans, like raccoons and deer—which can interact with humans and their property often enough to be considered nuisances. But are these now urban wildlife too numerous and running amok amidst the city backdrop, or is this actually bad press?
Just where are the deer?
The District of Oak Bay has been in the news often about a deer overpopulation problem. They’ve attempted a cull to manage deer populations, but as found in other municipalities, the cull had no lasting impact on the deer population but it did garner a public outcry. Management of the urban deer population has been highly polarizing—some people want them to stay, some people want them completely gone—but the management of urban wildlife is predicated on the knowledge of population size.
can give wildly different estimates of the number of deer present in Oak Bay. Any
single human observer may see six deer in their yard one day and then none the
next—humans have a cognitive bias, the availability bias, whereby we note large groups without noting
all the absences in between—which inflates estimates. And, when trying to count
mobile species, you need to be sure that you’re not counting the same
individuals more than once. And if you don’t see a deer, can you be sure that
it’s actually not there as opposed to just hiding? Thankfully camera traps to
We divided the 10.5 km2 of Oak Bay into 400m grid cells, and we systematically placed one camera trap into each of those 39 grid cells. Each camera trap was a Bushnell infra-red remote digital camera, secured to a tree between 0.5-1.5 m above the ground. Human observers can miss deer that are well hidden or might miss them in time (e.g. once the observer goes home for the day). The motion-activated camera traps are able to take photos throughout the day, eliminating those kinds of errors. The systematic design we used also allows us to differentiate between areas with high numbers of deer and those without deer—and ensured we could collect multiple observations of the same individuals across space—allowing us to get a good idea of space use. In addition to the cameras, we put GPS collars on 20 does to get an idea of home range size in Oak Bay, but the GPS collars had double-duty, to “mark” our known deer population. By measuring how frequently we detected marked (collared) animals at a camera station, compared to the number of unmarked animals, we could get an accurate estimate of population size.
Combining this systematic camera trap design with GPS collars has allowed us to generate the first, precise and robust estimate of CBTD population size in Oak Bay’s history. So then, just how many deer are running rampant around Oak Bay? Our analyses tell us that there are just under 100 deer (97 is the median, 95% confidence intervals between 72-128) and that they aren’t distributed equally across the municipality. Most deer spent their time within a 0.14 km2 area, and the largest average area a deer would use is 0.64 km2—significantly smaller than the home ranges they would use in wild environments (~140 to 1,770 ha.). That tells us that Oak Bay residents are seeing the same deer over and over, rather than seeing hoards of deer just once as they migrate through a large area.
With a definitive understanding of how many deer actually reside within Oak Bay, and where they are concentrating within the municipality, management can now be tailored to be cost-effective and successful. This fall, we administered immunocontraceptive (IC) to 60 does, and in the spring of 2020, our camera traps will be able to tell us if this birth control method was successful. If only our control group of does have fawns at the heel on camera trap photos, then we should be able to conclude that IC can be effectively administered as a non-lethal urban wildlife management technique—for Oak Bay, the Capital Region District of Vancouver Island, and other municipalities across BC that are struggling with their own urban deer management. We’ll be looking forward to seeing what the spring 2020 camera trap photos will reveal!
This piece was reposted with permission from WildCAM.
As another year of changing seasons comes to a close, the UWSS would like to wish everyone a very Merry Christmas, Happy Hanukkah, or perhaps just simply a celebration of the beauty, peace and balance that we so often find in nature.
We are sharing this video that reminds us of the unseen movements of wildlife, captured by a camera similar to the ones used in the current urban deer project we are conducting.
May the next year bring joy and happiness to you all.
May the next year bring happiness and joy to you all.
Over the past two years, you may have got used to seeing 20 does wandering around with collars that have four large tags in a variety of colours hanging from their necks. These deer are the control group for the Oak Bay Urban Deer Research Project and the collars are equipped with GPS, which has allowed our research team to track the does and collect data on their movement patterns, numbers, density and more.
This fall, 60 does, not including the control group, received an immuno-contraceptive (IC) vaccine. In order to be able to evaluate the impact of IC on the deer population, these does were fitted with a simple collar, as well as ear tags. The collars and ear tags are colour coded in order to allow for individual identification and give our researchers precise information.
The two collars fit very differently. The 20 GPS collars are quite loose, to allow for movement of the collar when the deer are moving and eating, due to the GPS “box” and the tags.
The IC collars do not have a large GPS box on them, or tags. Instead, the identification system is based on the colour of the collars, and the colour of two numbered ear tags that were also put on the does (along with one small provincial tag). These collars fit high on the neck and are quite snug to reduce chafing – we are always looking for ways to ensure the comfort of the deer. The fit of these collars minimizes movement as it’s not necessary without the tags and GPS box. The collars fit like a dog collar, allowing for two/three fingers to slide comfortably under the collar. They were fitted very carefully by our wildlife veterinarian, Dr. Hering.
We have had a few concerned citizens contact us that the collars seem too tight, and that the neck of the doe is “bulging” over the collar. Dr. Hering followed up on one such sighting a few weeks ago, and he was still able to easily slide his fingers under the collar – it was just the winter fur that has grown in since the field work that made it look tighter. He was happy to report that the fur and skin under the collar were in good shape.
Despite the collars appearing very snug, a few of the collars may have still been loose enough to slip down the neck a little bit, in fact unintentionally tightening them. We don’t think this is an issue and that it’s still the fur that creates the illusion of the collars appearing overly tight. However we have really appreciated citizens taking photos and letting us know of their concerns so that we can follow up. We recently had a reporting of a doe in the Falkland area that Dr. Hering would like to check out. If you see her, please note the colour of her collar and ear tags and send us an email at email@example.com so that we can locate her and have Dr. Hering evaluate.
Some people have also expressed concern that the collars will tighten as young deer grow. The collars on younger deer were fitted a bit more loosely to allow for growing over the winter. The collars all have a “rot off” so that over time the elements will cause the material to break down and the collars will drop off. For more information on the collars please go to https://uwss.ca/faqs-about-collars/ .
As always, we are grateful for the involvement of the community in this project. Our goal is to provide evidence-based, scientific information without compromising the deer. Their well-being is our first priority. If you do see a doe that concerns you, please contact us. It would be very helpful if you could note the collar colour and ear tag colour/number if possible. If you can safely take a photo, that would also be very helpful.
The Climate Emergency has an impact on all of us, often in ways we don’t necessarily recognize. Alina Fisher, communications expert for the UWSS (UVic PhD student), is a signatory on the open letter in the journal BioScience, signed by 11,258 scientists from 153 countries, declaring “clearly and unequivocally that planet Earth is facing a climate emergency”.
We know that the climate emergency is necessitating change everywhere, including our local communities. For instance, while people are looking for deer resistant plants for their gardens, what is often actually occurring is that past staples of the garden are being replaced with drought resistant plants – often with a return to native plants.
Although the indigenous Black-tailed deer have always been here, we don’t know exactly why their numbers have increased. There is a common belief that loss of their natural habitat is one of the most likely culprits, but we can also infer that Climate Change has had an impact too, with one outcome being a longer fawning season.
These are questions that our own scientists and others seek the answers to, and we hope that the Oak Bay Urban Deer Research Project might help us answer some questions, and see how the Climate Emergency affects not just us, but the wildlife that we are learning to once again co-exist with. We’re grateful to Alina for helping to bridge the gap between understanding climate change and recognizing the impact in our communities.
As Hallowe’en came and went, the immuno-contraception(IC) portion of the science-based Oak Bay Urban Deer Research Project came to a close for this year. What a successful September and October it’s been!
However, prior to the field work beginning in early September, there was a great deal of “behind the scenes” work, with Dr. Jason Fisher leading the research on strategies for studying deer populations, densities, space use, habitat selection, distribution and movement patterns. This research is an incredibly important component of this multi-year research project as it gives not only this community but others, information on urban Columbian Black-tailed deer ecology that has not been known before. All of this information is helping wildlife biologists, the province and other communities understand more about the indigenous urban deer populations in our midst. It’s important to remember that while many of us rarely saw deer in urban setting as recently as 10 years ago, they have been on this land for thousands of years, as indicated in First Nations historical records.
To that point, we are proud to have received the endorsement of the Songhees Nation for IC as the best management tool for the indigenous black-tailed deer population.
A first set of data, collected from twenty GPS collared does and 39 motion sensitive cameras was analyzed last winter (see preliminary report https://uwss.ca/our-research/ ) , and an expanded dataset will be analyzed this coming winter and after fawning season ends next summer. The next set of data will help our wildlife scientists better understand the fawning rate and population structure (e.g. ratio of bucks, does, and fawns in the population).
While the important research continues, the next step was to actually provide IC to does this fall, with the number of does determined based on the initial dataset. Although we had a permit to IC up to 80 does, we knew from the preliminary report that that would be the high end of the number of does, particularly as a control group of 20 does does not receive IC. However we were prepared to treat as many as we could in the short window available for IC field work.
So what did IC actually involve? Between early September and the end of October, wildlife veterinarian Dr. Adam Hering, along with a volunteer field team including other wildlife veterinarians, Dr. Jason Fisher, and his team of wildlife biologists, grad students and community members, sedated and then administered an immuno-contraceptive to 60 does.
While the does were sedated and their vital signs carefully monitored, the field teams took blood and fur samples that are sent to the Province for analysis. The does were then collared and ear-tagged with colour codes for individual identification before the sedation was reversed. Beginning in mid-September and right through to the end of October, all but three of those 60 does received a booster shot that increases the efficacy of the vaccine to between 85 – 95%.
This means that next spring, we expect that only the does that did not receive a vaccine, as there were some, and the control group, will give birth to fawns. The post IC data collection will give us important information but it’s likely that there could be a reduction in the fawing rate by approximately 60 to 90 fawns (the younger ones would only have given birth to one fawn, and those that have reached their 4th birthday would likely have had twins).
Of the 60 does, 8 were fitted with a prototype GPS collar that we are testing for Margo Supplies, an Alberta company that works to provide proven solutions to wildlife management challenges. Margo Supplies has worked with both Dr. Fisher and Dr. Hering in the past, and we were delighted to have the opportunity to trial these lightweight and innovative collars – another example of how so many stakeholders have come together to develop and implement a scientifically-based urban deer non-lethal deer management strategy.
As of October 31st, this first year of IC came to a close. This is because there is a small window of time that we have to vaccinate does – after fawning season and the summer, but before rutting season begins, usually at the end of October. Our provincial permit therefore expired on October 31, and a new one will be applied for when we next go out into the field. We see signs that rutting season has begun now, and this is a good opportunity to remind everyone to give bucks lots of space over the next month – please go to our website https://uwss.ca/about-our-deer/ for information on how to reduce human-deer conflict.
The urban deer project in Oak Bay is funded by the municipality, the Province of BC, and through the volunteer work of the UWSS. It’s a research initiative, with the key focus continuing to be the collection and analysis of data that continually informs next steps. The community engagement has been overwhelming, with over 650 home-owners allowing field work to occur on their property, and citizen scientists helping locate deer for vaccinations and boostering.
The work of the UWSS as part of the unique three-way partnership (four including the community!) is being widely recognized as a positive and hopeful approach to managing urban deer. Continuing with this cutting edge and innovative research project led by Dr. Fisher will be key to ensuring its success, and will benefit not just Oak Bay, but also other communities across the CRD, BC and Canada, that are struggling with managing urban deer populations.
During late-fall’s rutting season, any “street sense” our urban bucks have developed is likely lost in a hormone-induced haze.
Their behaviour can seem irrational, but really they’re just single-minded. It’s important to be aware they might run out into the road, when that wouldn’t be their usual behaviour. They’re likely not even seeing you, they’re just following a doe’s scent, and if they see a doe or are following a scent, they’re not paying attention to anything else around them.
With that in mind, it’s important drivers, cyclists and others pay attention, especially around dawn and dusk, when deer tend to be more active.
While bucks are only interested in other deer, it’s best to keep your distance as you would with any wildlife:
When walking, give bucks extra space – Because a deer’s natural response to danger is to run, always leave it an escape route far away from yourself. Keep dogs on a leash and if you encounter a deer, keep your dog pulled in close to you, stop it barking if you can, and walk away from the deer to give it more distance. Always check your yard carefully for deer before letting your dog out.
When driving, watch the roadside – Drive as though you were in a playground or school zone; pay extra attention and reduce speed, especially when driving in unfamiliar areas at dawn and dusk. Scan ahead, looking for movement or shining eyes at the roadside.
When cycling, give yourself time and space – Take plenty of room so you can react to any unpredictable movement. If its safe to do so, pull out from the curb and give the deer a wide berth. Slow down, and just like a driver, scan ahead, looking for movement.
You might also see bucks rubbing their antlers on trees and fighting each other in demonstrations of strength. This can be loud and seem aggressive, so keep your distance from these paramours!
Election day may be coming up, but don’t forget to exercise your right to vote in our photo contest by 9am on October 19th!
Take a look at our gallery of 32 stunning photographs and choose up to ten of your favourite finalists; voting is by donation. While you’re there, pre-order a calendar featuring the 12 winning photographs, and/or cast a bid in our blind ballot auction to own a framed exhibition piece.
One lucky voter will win a night out to the Belfry Theatre with dinner at the Fernwood Inn, followed by dessert and champagne at Stages Wine Bar.
Thank you for supporting the UWSS in its work, and the artists behind each photograph. We couldn’t do what we do without our community.
Join us for the Exhibition Opening of our Photo Contest finalists! Enjoy a hot mug of apple cider and peruse the three categories: Wildlife, Natural Landscapes & Gardens of Victoria.
When? Oct 5 from 1-4pm
Where? 1442 Monterey Ave
Can’t make it? The photos will be displayed until the Awards Ceremony on October 19, or you can view our online gallery at uwss/photo-contest/. Vote for your favourite photo and and even win your own framed Exhibition Piece by casting a bid in our blind ballot.
The teams in the orange vests that you’ve been seeing out in the early hours of the morning have now successfully immuno-contracepted (IC) 51 deer, in less than three weeks! We have been finding the deer exactly where the preliminary report said we would, in the areas where there are the highest densities of deer, such as in the Uplands, around the golf courses, and some areas of South Oak Bay.
The field team, led by our wildlife veterinarian Dr. Adam Hering and our lead scientist, Dr. Jason Fisher, have used the same method of sedation that was used when we GPS collared 20 does in spring 2018. The deer are darted with a sedative, blindfolded once sedated, blood and fur samples are taken for the province, and after the necessary work is completed, a reversal drug is given that has the doe back on her feet within minutes.
This time however, while the doe is under sedation, we have also placed matching small tags in each ear, with a lasered number on them. There is also a smaller provincial tag which we’re required to mark the does with.
Along with being numbered, the tags are colour coded in an identification scheme that matches with a simple, coloured collar. These are not GPS collars and have no tags, their purpose is to help our wildlife biologists individually identify each doe both on the camera array spread across Oak Bay, and when we are looking for the does in order to give them an IC booster.
The identification collars fit high on the doe’s neck, and fit more snugly than the GPS collars. This is to minimize the chafing we noticed on some of the deer with the GPS collars. While the chafing is not a problem because the fur grows back in, we are always looking for ways to minimize the discomfort for these animals that we handle for the purposes of this cutting-edge research project.
To that end, we also inject lidocaine in each ear that numbs them for several hours so that the does don’t feel any pain from their colourful new ear piercings!
We expect to soon complete the first round of vaccinations on the does and then 2 – 6 weeks after the initial injection they will require a booster shot to maximize the efficacy of the immuno-contraceptive. The does don’t need to be sedated for the booster shot, so as long as we can re-locate them, the process will go quickly.
For more information on IC, please visit our FAQ page. If you have questions, or see a doe that is having an issue with her collar or ear, please email us at firstname.lastname@example.org.
If you’re out and about in the early hours of the morning in Oak Bay these days, you may spy a cluster of orange vests hard at work. It’s a significant moment for Oak Bay and the UWSS, as once again we’re out in the field – this time to administer an immuno-contraceptive vaccine (IC) to does in the Oak Bay area. Through our field research, we now know there are approximately 100 deer in Oak Bay. We estimate that around 60% – 70% are female, and we are aiming to vaccinate as many of these as we can before the rutting season begins in late October.