Northern Long-eared Bats Survive White-nose Syndrome in Man-made Habitats

Published in August 2021 @HarvestingNature

Since its first identification in a cave in New York in 2006, white-nose syndrome (WNS) in bats has caused significant population declines. White-nose syndrome is caused by a fungus, Pseudogymnoascus destructans, that infects the skin of the muzzle, ears, and wings of hibernating bat species across 35 states and seven Canadian provinces at present[1]. The fungus thrives in cold, damp conditions, perfectly suited for winter cave hibernacula. As it grows, the fungus causes changes in hibernating bats that make them become more active than usual and burn fat they need to survive the winter[2].

Northern long-eared bats (Nyctophilus arnhemensis) suffered a 95 percent population decline in New England between 2006-2012 due to WNS, and are now listed as “threatened” under the Endangered Species Act. Similar declines have been document in the little brown bat (Myotis lucifugus), among others.

While studying WNS and bats in their winter hibernacula, researchers tracked a small number of bats hibernating in home crawl spaces, basements, and other structures like concrete culverts in Martha’s Vineyard, Nantucket, and Long Island, New York. Luanne Johnson with Biodiversity Works reported that these bats were surviving the winter even when affected by WNS.

Crawl-spaces with dirt floors and homes with block foundations and BILCO style hatch doors are attractive bat hibernacula. Uninsulated foundations provide the proper temperature and humidity, allowing bats to hibernate all winter, where insulated foundations were used occasionally. Bats were tracked leaving the hibernacula occasionally in late winter in Martha’s Vineyard where water was available year-round, but the bats returned to continue hibernation and survived to spring.

Unlike WSN-affected bats wintering in cave hibernacula, bats also affected by WSN and utilizing man-made hibernacula maintained good weight and overall health throughout the winter. Some bats were tracked for up to three years without suffering severe complications from WNS. Another behavioral distinction between cave-dwelling bats and those selecting human homes is that the bats wintering in crawl spaces were tracked foraging much later in the fall, meaning these bats may have entered hibernation with better fat stores for a shorter hibernation period.

Additionally, Auteri and Knowles (2020)[3] found genetic evidence of little brown bats evolving with WNS. Allelic frequencies showed significant shifts in survivors for regulating arousal from hibernation, fat breakdown, and vocalizations.  Studies by Biodiversity Works and their partners suggest that bats hibernating in homes are less likely to succumb to WNS, allowing more time for bats to evolve to survive the disease. Therefore, Biodiversity Works is working with homeowners tolerant of bats to potentially treat the WNS fungus on their property and construct new hibernacula onsite if homeowners want the bats out of their basement. Also, they are working with contractors and homeowners to heighten awareness of bats hibernating in homes to minimize potential harm from construction or remodels.


[1] White-Nose Syndrome (usgs.gov)

[2] White-Nose Syndrome (whitenosesyndrome.org)

[3] First genetic evidence of resistance in some bats to white-nose syndrome, a devastating fungal disease — ScienceDaily

Flurries and Tail Feathers Inspire Future Upland Hunters

The Blue Mountain Pheasants Forever Chapter (Chapter) held their annual youth hunt at Clyde Shooting Preserve November 8th. The Chapter-sponsored event is typically held in September during the early Washington Department of Fish and Wildlife-designated youth hunt weekend, but fire danger this year resulted in the September hunt being canceled. A lucky break for this year’s attendees.

An inch of snow blanketed the Walla Walla Valley as folks awoke in preparation for the hunt. Twenty youth attendees and their families arrived from as far as Tri-Cities to attend the coveted event. Kit Lane, owner of Clyde Shooting Preserve, welcomed his guests in fine fashion with a bonfire outside, and a shelter with seating and large fire pit surrounded by a lovely brick hearth, blazing warmly to cut the chill.

Friends and families scattered about the yard, toasting hands and bottoms over the bonfire. Stories and laughter echoed among the buildings, setting a celebratory mood.

Fields were stocked and parties assembled to follow the skilled and stylish canines careening across the white-washed prairie. Snow fell in force as the initial hunters embarked, many first-timers eager to experience what the upland hype is all about.

Chapter volunteer Randy Snyder explains the retrieving basics to a youth hunter following a successful retrieve by his golden retrievers.

Through snowflakes and windchill, pointing dogs struck statuesque poses while flushing dogs encircled, pushing stunningly-plumed fowl skyward. Wily roosters took to wing as pump guns and doubles tracked.

The occasional bird came to hand by means of luck and skill, sometimes both cooperating harmoniously. Retrieves of all kinds, some at length and some nearby, aided young hunters in securing their airborne quarry. And true to the hunt, a number of birds exacted daring escapes into the hills surrounding the canyon bottom as hunters looked in awe and puzzlement.

Eight waves of hunters passed through the golden range. Experienced mentors handled bird dogs, orchestrated hunts and imparted lessons of firearms and shooting safety. All in attendance enjoyed opportunity and real-time coaching to improve accuracy.

Bird hunting is a balance of chaos for the well-seasoned, let alone someone new to working dogs and kicking up a colossal, boisterous, flailing bird capable of reaching 55 miles-per-hour flight speed in seconds.

While some first-timers were unable to connect, their skill across the hunt improved markedly, becoming accustomed to their scatterguns, dog behavior and the adrenaline-pumping rush of an explosion of cackles and tail feathers trailed closely by a flash of driven fur and wagging tails.

A savvy yellow lab retrieves a rooster to hand.

Hunters were all smiles as they parted the fields, eager for the warmth of the truck heater, excitedly recalling the events with a clarity known only to those stricken with the same fiery passion for the hunt. Fortunate hunters selflessly shared their bounty with their unlucky field mates. And talk of next year already on the lips of those eager for another chance.

The Chapter appreciates Kit and Cindy Lane, our membership and the assistance of other volunteer mentors who selflessly sacrificed their day to share the magic of the uplands. Without the support of these fine folks, and the revenue from Chapter fundraiser supporters, this coveted opportunity to inspire the hunters and conservationists of tomorrow would not be possible.

Haying Best Management Practices for Wildlife

Farming and habitat practices to maintain healthy CRP and alfalfa stands provides significant nesting and brood rearing benefits to upland game birds, fawning areas for deer, and nesting and roosting habitat for wild turkey in the early spring and summer. Long, overhanging grasses provide nesting cover while broad-leaf plants like alfalfa and other native forbs provide insect forage for fledgling broods and hens. These stands draw and hold birds but have been called “ecological traps” in areas where haying regularly occurs.

The term ecological trap refers to a beneficial condition that attracts wildlife, but results in additive mortality, affecting the population overall. Quality CRP and alfalfa stands fit the scenario well where haying normally occurs during nesting season.

As haying equipment approaches, a hen pheasant may not vacate eggs or chicks, rather hunker down and use her camouflage for protection as a tractor passes by. This leaves birds vulnerable to the following mower which may be offset from the tractor. Likewise, small mammals and deer fawns use similar camouflage techniques and experience similar vulnerabilities to upland birds.

Best Management Practices

To minimize the potential hazardous effects of haying on wildlife, the Natural Resource Conservation Service has developed a few simple best management practices.

1) Defer haying. Apply and maintain at least two of the following management actions specifically for improving or protecting grassland functions for target wildlife species.

  • Do not cut hay on at least 1/3 of the hay acres each year. Idle strips or blocks must be at least 30 feet wide.
  • For at least 1/3 of the hay acreage, hay cutting must be either before and/or after the primary nesting or fawning seasons based on state established dates for the targeted species.
  • Increase forage heights after mowing to state specified minimum heights for the targeted species on all hayed acres.

2) For all haying during the nesting/fawning season implement at least two of the following to flush wildlife from hay fields during the mowing operation:

  • A flush bar attachment will be required on the mower (see figure below).
  • All mowing will be done during daylight hours.
  • Haying pattern:
    • Begin on one end of the field and work back and forth across the field, OR;
    • Begin in the center of the field and work outward.

Following these simple practices can greatly reduce unintentional wildlife mortality, further increasing the benefits of environmentally friendly farming.

flushing bar

Image from the Natural Resource Conservation Service.

 

Upland Review

I developed a magazine with the idea of showcasing the annual activities and accomplishments of Blue Mountains Pheasants Forever, Chapter 258, through photo essay. I also included a couple additional hunting articles.

I retain the magazine as an independent publication with a plan of developing it into a free online magazine to showcase fledgling outdoor writers and photographers, and the beauty of upland bird hunting.

Give it a read at Upland Review.