After a very poor mast year in 2021 – where very few tree seeds were produced, most notably acorns – there may well be fewer Eastern chipmunks this season. Ariana van den Akker photo

I like to study, and keep track of, the population dynamics of Maine’s wildlife. I’ve often written about how we have amazing databases like eBird (from Cornell) to track bird populations with great precision, but it’s much harder to keep track of other species, especially mammals. It is often thanks to the number of inquiries or reports we receive that a snapshot (albeit a subjective one) can be seen at various points with different species.

So when Arnold Aho of Damariscotta wrote in recently with a question about the lack of chipmunks he is seeing in the yard, or specifically under the feeders, it seemed a fun one to ponder.

At this early point in the spring, I’d like to have more reports from around the state to know if there is an apparent lack of Eastern chipmunks and if so, how widespread. So for now, I’ll let you see if you’ve noticed this correlation in your areas, but I think the answer of the missing chipmunks is tied to events from last fall. Readers may recall I wrote about how it was a very poor mast year – that is, there were very few tree seeds produced, most notably acorns. This was noted by readers saying they did not need to clear acorns in their typically seed-covered yards, and from squirrels feeding on alternative food sources, like my pumpkins.

Chipmunks remain active through the winter, but typically stay underground, feeding on the food (including a lot of acorns) that they’ve cached. I don’t think it is much of a stretch to say that if acorns were hard to find last fall, then perhaps survival rates for chipmunks were lower than average this winter, and thus people like Arnold are seeing fewer around.

To expand further on these trends, we did have multiple large mast years before the fall of 2021 and this often leads to higher populations of seed eaters, particularly squirrels and chipmunks. Perhaps we were becoming biased by “above-average” abundances of chipmunks over the last few years, so now that we may be having a “below-average” spring, it is more noticeable.

Also: Anecdotal, or perhaps another bias by social media algorithms, but I’ve been seeing a ton of fox kit pictures this spring. Again, it is hard to know if their numbers are actually up, but if the abundance of squirrels the last few years has helped the fox population increase, it isn’t surprising that I’d be seeing more evidence on the internet. Unfortunately, it does make me feel a bit pessimistic about the survival rates of those cute kits if there aren’t enough rodents now to feed them all, but this is the natural balance at play.

Northern bobwhite. Doug Hitchcox photo

REASONS FOR STRANGE SIGHTINGS

Some of the birds we see in Maine have very interesting origins: some come from human introduction, some from range expansions due to climate change, and others are natural vagrants. Birds can come from all over, which leads me to a question sent in recently from Sue Beland form Saco, about a species native to North America, but not native to Maine: a Northern bobwhite.

Northern bobwhites are a medium-sized game bird with a range across the eastern half of the lower 48 states. They are most abundant in the south and west with the northeast extent of their range reaching into Massachusetts, though their population there has dwindled and is now restricted to Cape Cod. Even when they were more abundant, they never made it into Maine.

The reason Sue Beland and others are now seeing them in Maine is because they are released for hunting. There are several species of birds commonly released in Maine for hunting, including bobwhite and ring-necked pheasant. Each year, the Maine Department of Inland Fisheries and Wildlife releases around 2,000 ring-necked pheasants at sites across York and Cumberland counties before the start of the hunting season, which runs from late September through the end of the year. Survival rates are very low, but occasionally those that make it through the season will wander into people’s yards and attempt to survive the winter. Keep in mind that these are birds that were raised in captivity, so they typically won’t be too shy about being around humans and are no strangers to bird seed and free handouts.

We tend to get a lot of reports of these various released game birds in the fall because of the aforementioned releases, but spring reports are also common. This is the time that many hunters are training their dogs and will release other game birds that are better for that purpose, including chukar and less commonly Japanese quail (also known as “coturnix quail,” named after their genus). There is no hunting season for these later species, but they are considered “heartier” than the “fragile” bobwhites, and thus make better birds to train dogs to point.

While we can chalk all of these Northern bobwhite and chukar records up as released birds, it is helpful to keep track of the ones that are attempting to make it in the wild. Despite the continued releases, some of the southern and coastal populations of ring-necked pheasants are now considered “established” in Maine, and others may eventually follow, too. We’ve seen reports of chukars and bobwhites successfully nesting in Maine in the summer, though many of those birds are unable to survive the winters. Perhaps as our winters warm, these escapees will eventually find the conditions they need. In the words of Dr. Ian Malcolm, “Life finds a way.”

Do you have a nature question for Doug? Email questions to ask@maineaudubon.org and visit maineaudubon.org to learn more about backyard birding, native plants, and programs and events focusing on Maine wildlife and habitat. Doug leads free bird walks on Thursday mornings, 7 to 9 a.m., at the Gilsland Farm Audubon Sanctuary in Falmouth.