Back in the day we got snowed in last of nov. and it stayed till April Hares were abundant last few decades warmer winters maybe more rain then snow No rabbits last couple weeks mostly 50's couple 70's Would rabbits and hares come into heat in this warm spell I theorize on this because in town last February several people found nests of cottontails' Whats your thoughts?

I am certainly not trying to pass myself off as Gulo but I'll give you my opinion......and that's all it is

Of course we know that hare populations seem influenced to some degree by solar cycles. Cats seem to be also but that may be as a result of the hare cycle.
But in the case of estrus onset...........my guess is that it is controlled by photoperiod. Just like the onset of priming.

I am hoping Jack will see this thread and we can all learn something

eastern cotton tails were doing back flips over the other bunnies 2 weeks ago = now that is a good indication l'amour is in the air

My semi tame bunnies are chasing each other quite a bit ! When they aren't begging me for snacks...I do keep pellets out for them anytime they want any, though. They are so fun to pet

Jeff -

Much research over the past 100 years, mostly from the fur farm folks (mink and fox farmers predominantly) having to do with both fur priming and breeding cycles. As white17 has postulated, both priming and estrous cycles are controlled largely by photoperiod. There have been grand experiments, by variations in the periodicity of light, to bring mink into estrous twice a year instead of only once. Indeed, there shows some promise (I can't quote a source right now, I'll have to research it again) in ranch mink producing two litters per year. There seems to be a major influence that had to do with the angle and/or the amount of light that hits the pineal gland and influences estrous cycling.

People used to talk extensively about the "rut" timing in moose and other critters. Because that timing is largely controlled by shortening photoperiod, it happens (in moose, wolves, marten, or deer) on the exact same day every year. The activity we see varies (probably due to temperature) from year-to-year, but their ability to rut doesn't vary at all. We tend to generalize by saying "it's a late (or early) rut this year because it's been so warm (or so cold). It appears that temperature doesn't have a thing to do with the timing, it's simply what we see in their activity.

To answer your question, I don't think in lagomorphs (or anything else), estrous varies significantly due to temperature. It's all dependant on photoperiod. In snowshoe hares, there may be a response by the Salix (willows) in their production of toxins which in turn affects the cycles, but opens a whole 'nother can of worms that hasn't been fully investigated. I'll not go there.

As an example of photoperiodicity influencing breeding,, think about this. Ruffed grouse begin drumming their wings in early spring, trying to bring in females. To a much lesser extent, these grouse also go through a "false-drumming" period in the fall when the photoperiod is exactly the same as in the spring. They are really not going through another breeding cycle, but they have been "tricked" into thinking it's breeding time once again because of the similar photoperiod.

This rambling at all helpful?

Jack

Thank you, Jack, really like your input, always. Not rambling, but full of interesting multi level details.

Sorry, Jack. Didn't mean to distract your thread too much, I just love my bunnies

I remember when prof Roach from Wisc was doing snowshoe feeding behaviour in the Interlake area of Manitoba of supplement feeding and it's effect on production that cycles were 2 weeks early, unfortunately he died early driving up here so I lost contact with the remaining students and study.

When I attended UW Madison in the late 1960s and majored in Wildlife Ecology one of my profs was Dr. Keith who spent many years, time and hours in northern Prarire Provences of Canada working on the cycles. There were several theories back then on the 9-year cycle. I don't know where that has all gone since then. Grouse and snowshoes were major study species then. Also lemmings as they were more prolific and their populations would cycle or swing more and the predators would follow those swings as well.

Bryce

Many species, especially those of increasing latitudes, display cycles in their populations. However, to qualify as a true "cycle", the population ups and downs must be predictable. In North America, most mouse/vole populations fluctuate wildly (the highs more than 40 times the population lows) but they are caused by varying weather patterns, and they are not predictable in periodicity, thus, are not true cycles. Interestingly, populations of many voles in Europe/Asia (read Siberia, in particular) are apparently "cyclic". Why the difference?

Jack

Where I live there has been loss of habitat and rabbits are way down from where they were. Without going on and on about it in the 80's you couldn't drive somewhere without seeing a roadkill rabbit or having almost hit one yourself. Literally overnight in your headlights driving anywhere you would see a dead one along side the road or almost hit one darting around in the side ditch and then across the road. There used to be a dozen tame rabbits just bouncing around town for whatever reason too actually. Near the library and lumber yard.

Anyway about the time they went to no till farming, cutting out all the fence rows, bulldozing all the brush piles, tearing out all the railroad tracks. There used to be miles and miles of thickets along railroad beds that no long exists. When farm prices got high enough to justify spending time and fuel clearing the land that land got cleared. In doing so the cover went away and so did the rabbits. Now there are guys that still rabbit hunt and they are around don't get me wrong but they used to be everywhere.

All of that habitat is gone and so many kids learned to hunt by stomping through that brush chasing rabbits. Now a days kids think hunting means freezing to death, not talking, and trying to sit still as you wait for a deer to walk past. As a kid its hard to beat rabbit and squirrel hunting.

Not to mention a spike in Raptors. Seems odd that rabbit populations would go down and raptors would go up but here we are.

I think the ethanol plant and corn prices being high are to blame locally here. It really drove up the best farm ground in the state, made it valuable, and cleared it away for crops.

I think OhioBoy hit the nail on the head. An awful lot of the decline in rabbits (and, of course, upland birds) is not cyclic, but due to habitat loss through whatever means, often "clean farming". It's disappointing to watch, knowing those affected populations will never bounce back.

Jack

Thank You All, and yes in the 60's and 70's the farms were all small 160-200 acres rail and woven wire fences with 10 feet or more of scrub trees and weeds. Our winters here were predictable you had Bad or worse winters and the fence rows disappeared till April Thousands of acres have been cutover and regened to popple and balsam no bunnies .The 40 I live on is half cedar swamp which hasn't been touched since well I did find a crosscut saw grown into a tree and there was a few hares in it shot a snowshoe once and my 2 year old daughter cried that i shot the Easter Bunny She's 40 now and haven't seen a track most of those years
Appreciate your comments othewise I would'nt know whats happening outside of my little bubble

You nailed it Habitat is the number one control on wildlife population . And the best way to get anyone interested in hunting is to take them small game hunting. In the 1970's President Reagan's Sect of Agri said farmers need to plant from fence row to fence row They have removed the fence row double crop an bale any and all crop residual SO NO COVER EQUALS NO WILDLIFE Agri business now decides what to plant and many times the farmer is left with no choice to get on board or be left out

Jack, I have a question on beaver breeding. In western Oregon (open water year-round) breeding begins in the month of January, but my assumption is in the north it must begin after ice break up. How does all of that jive with photoperiods as ice break up is likely 2-3 months later than when they're actively breeding here?

So I’m guessing it’s rabbit mating season? That would explain the pairs I’ve been seeing while night hunting. I haven’t seen any copulation yet, but have seen plenty of pairs playing tag.