Study: Adirondack moose numbers low but stable
RAY BROOK — Researchers presented their latest data on moose in the Adirondacks during the Adirondack Park Agency's regular monthly meeting in October.
The state Department of Environmental Conservation estimates that there are currently 716 moose within Adirondack Park, with a 95% confidence interval of the population falling between 566 and 906. While Stickles noted that moose have been seen in other parts of the state, this data pertained specifically to the Adirondacks.
The APA heard from Jim Stickles, a DEC big game biologist who specializes in bear, moose and deer, and Cornell University biology doctoral candidate Jen Grauer. The state has partnered with Cornell researchers to conduct research on Moose throughout the state.
Unsustainable hunting and habitat destruction resulted in moose being extirpated from New York in 1892, according to Stickles. Almost a century later, Stickles noted that moose began making a comeback in the state; crossing over from Canada and northern New England states. This resulted in sporadic, but confirmable, sitings that increased throughout the 1980s.
The Adirondacks have not had the same success as neighboring New England states in growing the moose population, despite having a similarly supportive ecological environment, according to Stickles. Moose were completely extirpated from all of the lower 48 states except Maine at various points during the late 18th and early 19th centuries, according to the Wildlife Conservation Society.
Maine is currently estimated to have between 60,000 and 70,000 moose, according to the Maine Department of Inland Fisheries and Wildlife, an increase from the 90s, when it had about 29,000.
The Adirondacks have not had much of a population boom since moose returned, despite being a protected species that is not allowed to be hunted and having an ecologically supportive habitat.
"Our moose population seemed to be growing, but not growing at a rate that would be expected," Stickles said. "In other New England states ... moose really began to take off," he said.
"It's at least stable," he said. "We haven't seen any evidence that it's going down. If it's growing, it's growing slowly."
The population was estimated using helicopter surveys, which Stickles said have tended to be more efficient and accurate than using dogs to detect moose scat — the other counting technique they considered. Stickles said relying on dogs would have taken the entire summer, while the helicopter data could be gathered in seven to 10 days of flight time.
Grauer said the most common cause of moose fatalities in the Adirondacks was trauma — accounting for the majority of necropsies in all but three years between 2000 and 2022. Trauma includes deaths directly from vehicle collisions, or gunshot wounds.
Grauer explained that gunshot wounds are typically the result of DEC personnel or biologists needing to euthanize a severely injured moose or, in rare cases, self-defense from an aggressive moose encounter.
Parasites were the second leading cause of death in most years. Even if they are not the leading direct cause of death, understanding parasites' impacts on moose is crucial for biologists to understand the population health's full picture, including their reproductive potential, and assess best management practices for the species
"Parasites are a big deal for moose," Stickles said.
He described three main types that impact moose: brainworm, liver fluke and winter tick.
But Stickles doesn't see winter ticks as a major concern, despite their deleterious effect on moose in neighboring states.
They often die off after the first snowfall if they have not found a host to latch on to for the winter. Winter ticks have been observed on moose in the Adirondacks, but are not attaching in high enough numbers to harm moose as they have in New England, Stickles said.
When winters are milder, it gives ticks a longer "questing" period, or time to climb plants and wait to latch on to a host, before being killed by the snow.
Milder winters in the area have had an indirectly harmful impact on moose because they have led to a proliferation in the deer population.
Deer are genetically less adapted to the cold. Reliably cold winters in the past helped to keep their populations in check.
"We've had six or seven years now of mild to moderate winters. ... The deer populations have really increased significantly," Stickles said.
Grauer said that while she did not find evidence of much direct competition between deer and moose for survival, such as the populations fighting each other for food, a growing deer population still spells bad news for moose.
"We don't really have strong evidence for a direct effect of deer on moose. Rather, we're really seeing this kind of indirect indirection mediated by the parasite abundance," she said.
While deer host brainworm and giant liver fluke parasites, they have evolved with the parasites to not be physically harmed by them, according to Grauer. The parasites are spread to moose, which have not adapted like deer and are subsequently harmed. The parasites are deposited in deer feces, which snails and slugs feed on and then shed the parasites on plants that moose feed on, picking them up.
"Both of these seem to be the most pernicious parasite infections we see in the area," she said.
Grauer said her research showed this was especially the case for brainworm.
"What we were finding for brainworm is that the probability of brainworm infection was tied to our index of white-tailed deer abundance on the landscape. ... This is a pretty clear trend," she said.
Grauer summarized that the biggest killers of moose in the Adirondacks were vehicle collisions and parasites. While her research did not focus on collision mitigation efforts, she commended the state's road sign placement warning drivers to be alert for moose.
"Those are actually really well-placed for where we're seeing most of the moose occur," she said.
Stickles encouraged people to continue reporting what they see.
"We're absolutely interested in sightings from the public," he said.
