Oak Bay’s immunocontraception program has cut deer numbers in and around the municipality by 40 per cent since it began in 2019.
The Urban Wildlife Stewardship Society (UWSS) continues to analyze data from the program’s third year and aims to pursue a sustainable future for deer and residents alike. This year’s focus will include deer habitat use before and after contraception, fawn and adult deer abundance after three years of sterilization, and plans for science-based, long-term and non-lethal urban deer management.
UWSS research team helper Alina Fisher said contraception, GPS collars and camera traps were used to reduce the approximately 100-adult-deer population to about 60 between 2019 and 2021.
“I’m hoping to see a sustained reduction in fawns every year,” she said, adding population numbers for 2021-22 are still being finalized. After the first year, the numbers dropped to 58 per cent of the original population.
“In that time, we saw a huge change in the number of fawns being born.” Given their low survival rate, she said, “it’s not like you see a fawn and that equals one deer the next year.”
Today Fisher sees the program receiving a more positive reception and insightful questions from the community than when it began. A temporary pause on the program was initially planned so researchers could rule out environmental factors that may contribute to deer population growth, but Fisher said Oak Bay council chose to keep it running to maintain lower numbers and will help decide what happens next.
In Oak Bay, does no longer carry the bulkier GPS collars. “They were big and they had battery packs in them and they fell off after three years’ use.” Deer collars and tags now come in “every colour on the rainbow,” she said, so they stay uniquely identifiable.
Does sporting pink tags are mostly unsterile “control deer,” which purposely haven’t received contraception to help UWSS track their movement in comparison to sterilized does.
In terms of other options, culls prove largely ineffective and translocation merely moves the problem from one community to another, Fisher said. A sudden absence of deer somewhere may prompt does in other areas to fill that space, capitalize on reduced food competition and even team up.
“There’s no silver bullet in this, or else we would’ve found it.”
The BCSPCA supports such non-lethal measures as landscape changes, fencing that deer can’t see past, motion-activated lights and sprinklers, and the planting of fragrant, prickly and poisonous plants such as daffodils, lavender and rhododendrons. It also supports the UWSS program, a spokesperson confirmed.
The Ministry of Forests stated in 2016 that alternatives to fertility control, such as culling, must be used to achieve quicker results and that sterilization requires capturing, treating and surveilling 70 to 90 per cent of does for long-term population change. Its Provincial Urban Deer Operational Cost-Share program matches up to $100,000 annually for communities developing socially acceptable deer management solutions and will soon let municipalities apply for the 2022-23 year.
In a recent statement to Black Press Media, the ministry said it continues to partner with Oak Bay on the contraception program “on a trial basis before determining next steps.”
While a long-term deer management plan for Oak Bay remains in the works, Fisher cautioned the community about resident fawns growing older and, as a result, more mobile.
“Like most middle schoolers, they’re not going to make good choices,” she joked, speaking from experience as a mother. “Keep your eyes peeled for those goofy fawns.”
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