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Entries in northern long-eared bat (2)

Friday
Mar132015

Saving the Northern Long-Eared Bat From Extinction

White-nose Syndrome (WNS) has stricken the Northern Long-Eared Bat of Maine and state and federal regulators are taking steps to protect the bats and restore the population.  At present, the bats are proposed to be listed as threatened or endangered on both the state and federal level.  Decisions are pending this spring.

What is White-Nose Syndrome?

The recently identified White-Nose Syndrome (WNS) affects bats who hibernate in colonies during the winter, and is caused by a fungus called Geomyces destructans. The name refers to how infected bats develop a white fungus on their muzzles.

WNS was first identified in New York and it has spread throughout the northeast US, through Maine, and even into Canada. WNS has killed more than a million bats in the northeastern states. In many areas where the long-eared bats hibernate, ninety to one hundred percent of them have perished from WNS.

While the fungus that causes WNS is not well understood, the Maine Department of Inland Fisheries and Wildlife believes that spores attached to humans may have brought the disease to uninfected areas. They have requested that climbers and spelunkers curtail their activities.

 

Meet the Northern Long-Eared Bat

Because these bats have become so rare, few in Maine know what they look like or where they can be found. Their bodies are about 3 to 3.7 inches long, with a wingspan of 9 to 10 inches. Their fur is usually medium or dark brown on the back, and tawny or pale-brown on the underside.

While they may use other habitats where they are less susceptible to WNS, most northern long-eared bats hibernate in large caves or mines during the winter. They prefer those with big passageways and entrances, high humidity, and no air currents. In the summer they venture out to find food and mate, seeking shelter in hollow trees and logs or rock crevices, and sometimes in barns and sheds.

What’s Next for These Bats

Initial contamination of caves in NY may have been from cavers who brought fungi from Europe but most of the spread has probably been bat to bat exposure either during summer or during winter in infected caves.

Humans have not yet found a way to fix the damage, or even necessarily prevent the further spread of WNS. Listing the bats as endangered or threatened will not solve the problem but highlights the seriousness of the situation and prods us to look for solutions.

Thursday
Jul312014

Endangered Bat – What Should Woodland Owners Know?

The northern long-eared bat (NLEB) has been proposed for listing under the federal Endangered Species Act by the U.S. Fish and Wildlife Service. So what should a woodland owner know? I recently sat in on a discussion of bats in Maine, specifically the NLEB.

This bat can be found south to Georgia, north to Quebec and as far west as the Canadian northwest. It’s medium sized, very maneuverable and adapted to feed on insects beneath the forest canopy. During the day it roosts in trees, most often under tree bark or in small trunk cavities. And like other bats, itPhoto credit: Al Hicks, New York Department of Environmental Conservation feeds at night. While NLEBs have been found throughout Maine in summer, they congregate in the fall and hibernate in caves, mines, and sometimes human-made structures. These sites are called hibernacula.

Based on hibernacula counts, there’s been a decline of more than 90% in Northeast NLEB populations in just the last few years, caused by a fungus known as White-Nose Syndrome (WNS). It’s thought to have arrived from Europe on cave-exploring  equipment and was first reported in New York State in 2006. Bats in Europe evolved with the fungus, but not here. The fungus doesn’t kill the bat, but causes irritation while hibernating. This causes them to wake more frequently and use more energy, and because reserves are tight, most won’t survive without additional food. But insects are not available in winter, and the problem is compounded because bats form large colonies, where WNS spreads.

Bat species that hibernate in mines or caves are susceptible to WNS. In Maine, those species are big brown bats, little brown bats, northern long-eared bats, tri-colored bats, and eastern small-footed bats. The other species haven’t been affected by WNS to the same extent of NLEB, likely due to specific characteristics and habits. Two other bats in the same genus as NLEB, however, are being closely watched – the little brown bat and eastern small footed bat.

Final determination on listing was due in October, but has been delayed until April. Given the sharp decline, however, it seems certain the bat will be listed as endangered. USFWS then usually identifies critical habitat. In this case, though, the bat is a generalist, found throughout the forest. It may roost in groups on trees, but it’s almost impossible to tell which ones. The guess is that with listing, the designated critical habitat is likely to be the known winter hibernacula; in Maine, mostly natural caves. The exact locations are kept secret to avoid human disturbance, but such caves aren’t common. It’s possible a zone of up to five miles could result in regulating some activities.

If you own land in a critical habitat and there’s a so-called “federal nexus,” you’ll need to make sure proposed activities won’t adversely impact any identified critical habitat. A federal nexus could be created if you receive technical advice, permits, or federal financial support. For small woodland owners, this would commonly involve cost-share activities, a management plan or timber stand improvement. Activities might have to be modified, though they would likely be allowed.

The second way an endangered species designation could affect any landowner is a “taking.” It’s a crime to kill, harm, harass, pursue or remove from the wild an endangered species. This applies anywhere the species exists, and isn’t limited to designated critical habitat. Bats are born between June and mid-July, and fly when 18-21 days old. So felling a tree with flightless bats could result in a taking.

The challenges are obvious. Bats are small, blend in, and there’s nothing to identify roost trees. With the bald eagle, a species once endangered but recovered, the nests are obvious; not so with bats. If the NLEB is listed as endangered, there are likely to be best management practices developed to reduce the likelihood of bats being injured. There’s also the possibility of a conservation plan that would set up an “incidental take” permit for forestry. There’s been little research done on NLEB, so plans on how to promote recovery of the populations will be based, in part, on the listing in place for the endangered Indiana bat, which does not occur in Maine but has a similar life history.

The loss of any species is regrettable, and bats are efficient predators of insects. If a bat species disappears, will certain insects increase? Other species may fill part of the void, but no two species serve the same function, so the impacts are unknown.

The story of the northern long-eared bat is also a solemn reminder of the enormous damage that can result when an insect or disease from some other part of the world is brought to places where there are no natural enemies or controls. We’ve seen dramatic impacts before, notably with Dutch elm disease and chestnut blight. We face current threats from the Asian long-horned beetle and emerald ash borer. It’s a reminder of the importance of strong protections against accidental introduction that could alter the forest and the life forms that inhabit it. 

Tom Doak is the Executive Director of SWOAM - Small Woodland Owners Association of Maine.  SWOAM is the only statewide organization dedicated to supporting the interests and serving the needs of Maine's 100,000 owners of small forested parcels (from 10 to 1,000 acres in size).