New Hampshire Nature Notes
by Eric Orff

At 6:30 this morning the thermometer read 40 degrees. Its been a long time since that has happened in this summer of drought and relentless heat. It was only about a week ago, as I recall, that we had another 90 degree day putting our summer 90 degree days around 25, just below a record. And the nights this summer just seemed to be as sweltering as the days. I can tell you our poor moose were on my mind many of those days and nights. 

It is a well know fact that our warming winters have contributed to a significant decline in moose numbers across New Hampshire over the last decade and a half that this state's moose population has declined from about 7,500 moose to closer to 3,500 today. Most folks attribute much of this decline to our shorter winters causing an uptick in the winter tick numbers that are literally killing off our moose, especially the calves. According to the Fish and Game Department moose biologist Kris Rines it is the lack of snow in April, when the female ticks drop off to lay their eggs, and a late winter with no snow in November when the baby ticks are seeking moose, that is the root of much of the problem. No snow when females lay their eggs in the spring means lots of baby ticks. No snow late fall going into winter gives the baby ticks much more time to get on a moose. Last fall there was no snow on the ground up north until late December giving the baby ticks an extra month and a half to find a moose. As a result according to the ongoing UNH/Fish and Game moose study there was an average of 42,000 ticks on each moose. Moose calves cannot support those numbers and 81 percent of the moose calves died last winter along with nearly 25 percent of adult cows.

But winter moose mortality really only tells half of the story as to why our moose numbers are down half of what they were 15 years ago. Yes our shorter winters are a big factor but so too are our ever warming summers. The fact is moose stop feeding when temperatures reach the high 70's. And do moose feed, some forty pounds of browse a day. Lets put it this way. If you filled your bathtub with leaves and twigs a moose would eat it all in a day, or make that a night.

And this summer's high temperatures have no doubt further impacted our dwindling moose herd. Just a few weeks ago while watching the ten o'clock evening news I could see that almost statewide temperatures were still in the 80's. At these temperatures moose cows cease to feed. As it already Is, because of our warmer summers, adult cow moose body weights are down causing a significant reduction in moose calve births. The percentage of cows giving birth to twin calves was down to only 11% when the 2002 to 2005 moose study was conducted by Fish and Game. In the last three summers of the current study NO twinning is now taking place. And the calving rate has declined from 75% of adult producing calves in 2002 to only 54% last year and 60% this year. So this summers heat wave lasting weeks with temperatures at 80 degrees at ten o"clock at night will only further reduce cow weights and future reproduction.

So we really have a double whammy on our moose population. Fewer moose calves are being produced by our underweight cows and a much higher death rate is killing off the few calves that are born. In fact the most recent population model that I saw presented by one of the moose study scientist predicts that given the current winter mortality factors, AND the loss of reproduction due to warmer summers, our New Hampshire moose population will essentially be gone by 2045. That's right, in less than 20 years moose will be gone from this state save for a remnant population. How sad of a legacy we are leaving our grandchildren.

We all must do our part to address climate change. Through the Regional Greenhouse Gas Initiative and the EPA's Clean Power Plan we can cut carbon and make a difference. Each of us can in some small way help save our moose for the future generations. Please do your part.