Where Have All the Bats Gone?

During the late 1960’s and throughout the 1970’s, my Mom and I would float offshore of a beaver lodge at dusk, watching the tree-eaters work and slap their tails.  As we drifted in our canoe, the air was filled with dozens of bats gobbling up mosquitoes and other insects.  The bats were so abundant that it wasn’t unusual for one’s wings to brush my hair as it chased its prey around my head.  It has been a couple of decades since I saw bats in those numbers on Temagami, and I’ve wondered what became of them.

Most people have heard of white nose syndrome (WNS) which has been killing bats in Canada since 2010 and in the U.S. since 2006.  WNS is caused by a fungus which grows on bats’ noses, ears and wings while they are hibernating in groups during winter in caves, mines and wells (called hibernacula). The fungus can remain viable for years in bat caves and on spelunkers’ gear.  WNS kills bats by a complicated set of effects causing them to wake during winter and starve.  WNS is carried from bat to bat and by humans moving from contaminated hibernacula to clean ones.  WNS has been called “the most devastating epizootic [epidemic] wildlife disease of mammals in history” by scientists.

Four Ontario bat species were listed as endangered in 2014 due to WNS: little brown myotis, northern myotis, eastern small-footed myotis (Myotis is the genus name of these three species), and the tri-colored bat.  Although no one knows how many total bats of each species lived in Ontario before and after the advent of WNS, counts from hibernacula where counts were done show that populations have declined 75-94%, depending on the species.  Other threats to bats include human destruction of hibernacula, of summer maternity roosts (females have one young/year and roost in groups during spring and summer), of feeding areas, direct killing by humans, and by wind turbines.  All of these threats are now more significant, because so few bats have survived WNS.

Bats provide a vital service in the form of pest control.  The value of their services is estimated to be $100 million to $1.6 billion in Ontario alone.  Also, increased numbers of mosquitoes contribute to increased mosquito-borne diseases.  

Is there any hope for bats?  WNS is moving westward and northward in North America, and preventing its spread offers the greatest hope of protecting unaffected bats.  A very small proportion of the Ontario bats already hit by WNS seem to be genetically protected from contracting the disease.  The Environmental Commissioner of Ontario (ECO) published a report entitled BIODIVERSITY UNDER PRESSURE: WILDLIFE DECLINES IN ONTARIO (2016) in which the Ministry of Natural Resources and Forestry (MNFR) is chastised for being too slow to define recovery strategies that might actually help save bats in the province.  Further, the ECO is pushing the MNRF to begin “broadscale biodiversity monitoring”, because “what gets measured gets managed”.

https://tla-temagami.org/tla-business/services/the-temagami-times/

Moose at Risk

A typical Temagami t-shirt has either a bear or moose on it.  Alarmingly, moose populations are declining throughout North America, and Ontario is no exception.   When the number of moose in Ontario declined to about 80,000 in the 1980’s hunting was restricted, and moose abundance rose to about 115,000 by the early 2000’s.  As of 2015, there were about 92,300 moose in the province, a 20% drop.  Near Cochrane and Thunder Bay, moose numbers declined 60% and 50%, respectively, over the last decade.

While there are likely multiple causes for the decline in moose populations, a central issue seems to be climate change.  Moose are highly cold-adapted, and a warming climate brings heat stress and increased parasites that can kill moose.  An example is found in New Hampshire where 41% of moose deaths in 2002-2005 were attributable to parasites, particularly ticks, which thrive under warmer conditions.  Moose do best in a mosaic of variable habitats.  First Nation elders have said that the longer a forest goes without burning, the fewer moose there will be there, so fire suppression could be a factor contributing to lower moose numbers.  

The main action MNRF is taking to boost moose numbers at this time is to limit hunting.  Thanks to a huge public outcry, MNRF discarded a potential plan to increase hunting of wolves and coyotes in Ontario.  Decades of research have shown that reducing top predators causes massive ecological disruption and does not reliably increase prey populations over time.  The 2016 ECO report (see bat story) criticizes MNRF for its short-sighted, uninformed approach to moose management.

https://tla-temagami.org/tla-business/services/the-temagami-times/