If anybody here has a wildlife biology background help me out here with this thought I've had all winter. Since it's been a ridiculously warm winter with at most 10" of snow combined (most being yesterday) is that a help or hindrance on the deers survival? I like to fantasize of a absolute banger of a spring for fawn production, at the same time they didn't have the snow to help insulate them in their bedrooms. What say you smart folks?
Any biologists in the house? Deer number question.
- Thread starter trapoholic
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Years ago I attended a discussion where a deer biologist said, and I'm paraphrasing... Once the snow gets so deep, deer are better off laying down & starving until spring. They expend more energy trying to get around for what little food they can find.
I would like to think this spring will be a banner year for fawn production, our deer numbers are low here... The other consideration is predation, there's a fair number of coyotes around & I wonder how the lack of deep snow affects them getting around?
Cheers
Jay
I would like to think this spring will be a banner year for fawn production, our deer numbers are low here... The other consideration is predation, there's a fair number of coyotes around & I wonder how the lack of deep snow affects them getting around?
Cheers
Jay
Hard packed deep snow is hard on deer. Slow going constantly breaking through the crust. Easy prey for the coyotes as they can run across the snow. Snow here deer are capable of dealing with as it’s not deep enough to give the coyotes the advantage. A lot of twin fawn around here the last two years.
The deer are fine with the cold, it's the deep snow that puts them at risk.
Wildlife Bio here (retired). Several good comments above.
This PDF downloadable link is one of the best references for white tailed deer in Ontario:
https://www.ontario.ca/page/forest-management-white-tailed-deer-habitat
Its context is forest management, but its foundation is WT deer ecology.
When the PDF links, download it onto your hard drive. Then Adobe should let you search on key words.
Example: Search on "snow" and you will find a ton of info related to your question (i.e. winter energy budgets and expected body condition of pregnant does in the spring, fawn birth weights, etc.)
"Winter Severity Index" for WT deer gets complicated, depending on who you read, and geographically where the analysis is being done. For example, southern boreal forest WT deer range and habitat and behaviour is going to be different than southern Ontario deciduous forest and farmland. There is no one magic number for snow depth and winter severity thresholds. However a basic starting concept is 40 to 50 cm for un-crusted snow depth. But deer have already changed their behaviour, physiology, and diet long before the snow reaches that depth.
Crust has already been mentioned above, and that can be a significant modifier for behaviour and mortality.
The predators also don't have to burn as much energy in the shallow snow and warmer temperatures. So making predictions is not easy. Local coyote and wolf population densities are a big factor.
This PDF downloadable link is one of the best references for white tailed deer in Ontario:
https://www.ontario.ca/page/forest-management-white-tailed-deer-habitat
Its context is forest management, but its foundation is WT deer ecology.
When the PDF links, download it onto your hard drive. Then Adobe should let you search on key words.
Example: Search on "snow" and you will find a ton of info related to your question (i.e. winter energy budgets and expected body condition of pregnant does in the spring, fawn birth weights, etc.)
"Winter Severity Index" for WT deer gets complicated, depending on who you read, and geographically where the analysis is being done. For example, southern boreal forest WT deer range and habitat and behaviour is going to be different than southern Ontario deciduous forest and farmland. There is no one magic number for snow depth and winter severity thresholds. However a basic starting concept is 40 to 50 cm for un-crusted snow depth. But deer have already changed their behaviour, physiology, and diet long before the snow reaches that depth.
Crust has already been mentioned above, and that can be a significant modifier for behaviour and mortality.
The predators also don't have to burn as much energy in the shallow snow and warmer temperatures. So making predictions is not easy. Local coyote and wolf population densities are a big factor.
Our local town deer are amazingly plump.
Hope the ticks don't get to them.
Couple years back there were a few fawns that were hard to look at.
Had three fawns born on our property last year.
One the year before and two before that.
We'll see what the doe brings us this year.
Hope the ticks don't get to them.
Couple years back there were a few fawns that were hard to look at.
Had three fawns born on our property last year.
One the year before and two before that.
We'll see what the doe brings us this year.
- Location
- Blaster land, Okanagan BC
The deer seem to be doing well this winter, lots of hay fields around me with minimal to no snow on them for deer to graze. Every night when I do barn/animal chores I see them regularly in my neighbors hay field above or one fenceline, hopefully it’s a strong year for fawns.
nowarningshot
CGN Ultra frequent flyer
Cue Seinfeld marine biologist, George pulling Titleist out of blowhole.
Great info thanks.
Just wondering your thoughts on supplemental winter feeding southern Ontario whitetails when snow isn't crazy.
CWD has hurt both Whitetail and Mule Deer populations in SW SK. Our winters haven’t been hard on them. Cougars and wolf population is on the rise to my knowledge. Coyotes are always plentiful here it seems. Antelope are doing well. Rare to spot elk and moose here but they’re around.
Depends on where in southern Ontario.
Warmer low snow years are definitely good for deer but the spring is the teller. If you were to get a large amount of snow between now and the end of march it could still be tough as deer have mostly used up fat reserves from their natural decreased food intake. We used to have a 50-50=50 rule where if you had 50 cm of sinking depth snow for 50 days you would lose 50% of the herd so a big snowfall now can still be tough.
The low snow also makes it very hard for predators like wolves of coyotes as deer are more healthy and can run in more directions rather than being restricted to already packed trails.
If you want to help deer I would suggest packing trails with a snow mo or ATV dragging an old tire, and felling young trees down to allow deer to have access to their natural food.
Here is a link to an old file on winter deer feeding in Ontario and explanation of winter severity index and how it may effect fawns. https://www.ofah.org/wp-content/uploads/2015/04/MNR-Guidelines-deer_winterFeeding.pdf
The low snow also makes it very hard for predators like wolves of coyotes as deer are more healthy and can run in more directions rather than being restricted to already packed trails.
Not necessary and in fact may be detrimental. Taking deer out of their natural decreased food intake early when food is actually not needed for survival can have consequences.
If you want to help deer I would suggest packing trails with a snow mo or ATV dragging an old tire, and felling young trees down to allow deer to have access to their natural food.
Here is a link to an old file on winter deer feeding in Ontario and explanation of winter severity index and how it may effect fawns. https://www.ofah.org/wp-content/uploads/2015/04/MNR-Guidelines-deer_winterFeeding.pdf
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I've seen more moose than I can remember this past few months, 6 yesterday from the living room window. Elk numbers are way up, I see a herd of 75 to 100 every few days and there are lots of tracks in the fresh snow from a few days ago. No deer here, but lots down in the grain fields. Coyotes are everywhere as usual, but above average I think. This is in central SK.
My opinion (which might be controversial), is that its never appropriate to feed WT deer (with one caveat - see last paragraph)
CWD has already been mentioned. One of the ways it is spread is by saliva mixing between animals, and that contact with saliva from infected deer happens when the deer are feeding in an unnatural way, such as sharing feed troughs of grain, or from hay bales.
In the winter deer are browsers. When they clip the end of this year's growth of twig, or this year's cedar branch tip, chances are the next deer is going to work on a different twig or cedar branch because the older branches and foliage are not desirable or often not palatable, so the likleyhood of contacting another animal's saliva is less.
Natural selection works. Artificial feeding of deer allows the weaker or less-adaptive individuals to survive and pass on their genes. In the long run, its best that the weaker and less adaptive animals die when they obviously cannot survive in the conditions that they live in.
If the winter range is in poor shape for abundance and quality of winter food, then that often is the result of over-population of deer in previous years. I am sure we have all seen browse lines in forests and woodlots where all the available quality food has been eaten. Perpetuating that degraded habitat structure with higher population densities is not doing the deer any favours. Better to let them starve and die (and physiologically speaking they are starving in winter anyway, losing weight). Deer survive the winter primarily by entering it in a fat and healthy condition. They do need some browse to fill their rumen and get to sustain their gut flora all winter, and burn less of their reserves, especially pregnant does. Eastern White Cedar is one of their primary stomach/gut fillers that gets them through (good filler but low nutritional quality), all the while losing weight because they are burning fat reserves from the fall.
Deer are behaviourally capable of long seasonal migrations between summer and winter ranges (sometimes 100 to 200 km's apart), optimizing their access to the best nutrition, and predator avoidance. Artificial feeding regimes can interrupt these seasonal movement behaviours. Fawns learn from their mothers. If the fawn does not seasonally migrate with its mother, the knowledge of that range and the way to get there is lost in one generation.
The only "feeding" I would consider is felling trees and leaving the canopy top there for the deer (and moose) to browse. I think most folks know about how deer and moose are attracted to hardwood logging operations. Logging, or if not commercial logging, but simply dropping hardwood trees on your property in winter, will add some natural quality feed to the local deer. Its a low risk for CWD because they are feeding in natural methods, clipping off only this year's growth or buds on each separate twig. I would focus on poplar and birch if possible. That reference I listed will provide other species to consider. And if you don't need the stem for lumber or firewood, I encourage topping the canopy only (if you have the skills and safety methods) and leaving the tall standing snag for the woodpeckers to create cavities for cavity nesters. With the canopy dropped and on the ground, it opens the ground that was shaded to sunlight which can promote alot of summer herbaceous feed, and the shrubs and young trees for winter browse. The downed top should be cut up and flattened next summer since the tips will die and dry out, and it allows more sunlight for regen of all the goodies for deer.
I dumped 3 coyotes in the middle of a run last deer season with the 06' mice and squirrels had real fuzzy nests this winter round there!
sam menard
CGN Regular
All good info! My pet peeve about feeding deer is that it can do more harm than good. Deer aren’t bears, and their 4 chambered stomachs are extremely sensitive to the introduction of new foods. In fact deer can die from the introduction of the wrong foods or at the wrong time of the year. Do a Google Search for “acidosis in deer”.
Cedar branches makes good deer food as their stomachs are usually used to eating it.
