/Expert explores the fascinating lives of bats
Bats fly with their mouths open due to echolocation not to any sort of aggressive tendency according to Brock Fenton who shared his passion and knowledge for the mammal at a recent presentation held by the HHLT./SUE TIFFIN Staff

Expert explores the fascinating lives of bats

By Sue Tiffin

Published June 7 2018

Utterly intriguing are the words BrockFenton uses to describe the small animals he's been studying for morethan 40 years but the crowd gathered at the Minden Hills CulturalCentre to listen to the professor emeritus of biology at Universityof Western discuss his passion might describe his lecture in the sameway.

He speaks quickly as though he's soused to giving this talk he could do so in his sleep but also maybeso that he can cover the wealth of information he wants to share withthe audience attending the Haliburton Highlands Land Trust's Exploring the Lives of Bats presentation on May 26.

Aroundthe world there are 1260 bat species – in Canada there are currently19 identified species of bats – eight in Ontario – and four ofthose bat species have been classified as being endangered.

“One of the recurring themes here ishow much we don't know about bats” he said. “A lot of thequestions we had in 1968 are still the same questions we have now.One of the neat things about bats is just when you think you knowsomething they remind you that you really don't. That can beembarrassing but it also makes life very difficult. If you're tryingto figure out what the conservation status is of an organism whetherit's a plant or a bat or anything you need to know how many thereare. We don't have that kind of information for any of the bats inCanada. We don't know how many there are today. We don't know howmany there were 50 years ago 100 years ago. So those are the kindsof questions we need to know the answers to and we just don't. Wedon't know how many there are but we know there are a lot fewer nowthan there ever were.”

Bats have been facing an unprecedentedpopulation decline leading the HHLT to launch a bat project lastyear to identify bat species and their distribution throughout thecounty. All eight species found in Ontario including the fourendangered species have been found in Haliburton County.

Although some bats in the wild can liveto be as old as 45 they face numerous challenges in keepingpopulation up right from birth.

Mating occurs in August or Septemberbut a female bat will store sperm in her uterus until afterhibernation when an egg becomes fertilized. Generally bats produceone offspring a year though some species have twins – which oftenhave different fathers – and at least one species can have up to fourbabies at a time.

Baby bats are basically 30 per cent oftheir mothers weight at birth and the mother produces 75 per cent ofher body milk every day – as Fenton explains that's the equivalentof a 45 kg woman producing 33 kg of milk a day.

“Mother bats are extremely dedicatedto their young” he said. “They invest a huge amount of time inthem.”

Despite that care there is a high rateof mortality for bats with 60 per cent not making it through thefirst year likely because they don't put on enough weight to make itthrough the winter.

Fenton spends much of his time even onvacation around the world photographing and studying bats in theirnatural habitats and has had the rare opportunity to see some youngbats with their mothers.

Though there is keen interest in batsbiologists and conservationists still don't know some basic biologyinformation about them such as whether they have young every yearor every other year and at what age they have their first young.

Fenton shares some of the photos he'staken on his travels throughout his presentation including theclassic shot of a bat with mouth wide open wings outstretched.

“When you see a bat like this flyingwith his mouth open it has nothing to do with a hostile threat”he explains. “The bat's producing echolocation calls as it fliesalong and it needs to have its mouth open to do this. My good friendis fanatic about protecting bats. He never likes to share images ofbats with their mouths open because it sends the wrong message. Butin this case it isn't an aggressive message. It's not like facingdown a doberman with its mouth open. Besides the difference in size –these guys are about 15 grams. It's just the way they get around.”

Identifying bats based on signals canbe tricky like identifying bird song.

“The nice thing about bats is thatthey use echolocation or biosonar” said Fenton. “That meansthey'll tell you all about themselves. You just have to learn how tolisten to what they're saying.”

It was in 1794 that Italian LazaroSpallanzani discovered echolocation or biosonar when he realizedthat an owl could not navigate around a room in which the candle hadbeen blown out but a bat could. Using a series of experiments thatincluded materials such as ribbons and bells he was the first toacknowledge the unique ability of a bat in getting around. In 1944Donald Griffin – with the help of since-developed bat detectorswas able to expand on Spallanzani's research. Echolocation – usingsound to see – is not something that is characteristic of all batsbut is also used by some whales some shrews some birds and someblind humans to basically detect a hard surface on a soft background.

“That's relatively easy to do”said Fenton. “You can do that. You know that if you go into a roomthat's empty even if you're blindfolded you can tell from how theroom sounds that it's empty as opposed to a room that has furniturein it it sounds different. So it's no big deal.”

Simple science figured out theecholocation and its intricacies including that bats can't broadcastand receive at the same time – the outgoing signal is so strong itdeafens the bats in the returning echo. As the bat gets closer andcloser its calls get short and shorter so the bat doesn't deafenitself. So bats design their calls very actively and then analyzeinformation in the visual part of the brain not the acoustical part.

“The guy or these guys had aquestion” said Fenton. “It isn't that they had a lot of money tobuy fancy equipment. Ribbons and bells and a simple bat detector. Ifyou have a question and a way to manipulate things you can find outan answer. It's a good indication of how science works and oftendoes.”

Bats eat a vast array of insects butthe technique used to analyze bat droppings and determine whatthey're eating doesn't tell how many insects they're actually eating.

“The disconnect is that people thinkif they have bats they won't have any mosquitoes” said Fenton.“We don't have any evidence of that.”

Throughout the presentation Fentonnoted characteristics believed to be true of bats that aren'tparticularly factual.

“Bats see really well so when peopletalk about bats being blind that's just a mistake” he said. “Wedon't know of any bats that are blind.”

As far as scientists and researchersknew bats went south in the winter – but they didn't know how farsouth they go just that they go. Using motus tags moreunderstanding of bat travel has occurred through tracking theirmovement.

“One of the things we're discoveringit that the anim als don't read the literature” said Fentontelling a story of a hoary bat that should have been going southbased on our understanding but instead went to Windsor for theweekend and then turned up in Niagara Falls. “So a motus tag tellsyou all kinds of things that the animals are doing that we neverknew. And of course this only makes it more interesting because allthe things we kind of take for granted. The animals are on such ashort energy budget how could they possibly do that well it turnsout the bats don't read the literature and it turns out that birdsare just as bad they don't pay any attention to what everybodythinks they do.”

Besides a high rate of mortality afterbirth bats face other challenges that make them particularlyvulnerable from a conservation point of view.

“People tend to be afraid of batstend to think they're dangerous” said Fenton. “There doesn'tnecessarily seem to be any good reason to think those things butthat affects people's views of things and then affects the viewpeople have on the animals.”

Though bats like any mammal can carryrabies not all do and bites are uncommon. Bats can transmithistoplasmosis a lung disease but it's also possible to pick thatup from pigeon or chicken droppings. According to Fenton bats simplyhave poor public relations.

Wind turbines can be bad news for abat but that risk could be reduced if wind companies would reducethe cutting speed to 10 metres a second.

“We have eight speciesin Ontario but we do not know how many there are” said Fenton.“So if you find 10 hoary bats dead under a wind turbine you don'tknow if it's 10 of 100 that flew over or if it's 10 of 15 that flewover. You have no way of knowing. It makes it very difficult to putwhat you're seeing into perspective. But it's not getting struck bythe blade that kills the bats it turns out the negative pressurebehind the blade causes an embolism so basically their lungs explodeand that doesn't do them very good at all.”

Unfortunately for huge numbers of batpopulations white nose syndrome was introduced to the United Statesfrom Europe likely by accident in 2005.

“It's really bad news and theredoesn't seem to be any good news in that story” said Fenton whorelayed a story of researchers in New York studying bat populationsin three caves in that area. “In March 2005 they go into one ofthose caves and instead of 30000 live bats on the ceiling there's30000 dead bats on the floor. And this is what was happening to thesites there. By 2010 it was here in Ontario. The really bad news isthat by last week it turned up in Newfoundland. And then last week italso turned up in Manitoba so it spread bat to bat.”

Fenton has seen a decline in batpopulations in caves near Renfrew – where once he saw tens ofthousands of bats in those caves now he sees a couple hundredestimating about a 95 per cent decline in the population of somebats.

“It's only bats that hibernateunderground in caves and mines that are exposed to it or vulnerableto it” he said. “The other bats probably aren't affected by itat all. Not because it doesn't get them but because they don't evergo there. It's hibernating underneath that matters.”

A bat in the winter sound asleep hasa heart rate of about five beats a minute. The same bat's heart whenthe bat is flying in the summer beats 1200 times a minute.

“What's important for hibernatingbats is to not be disturbed because to wake up from freezing coststhe bat as much energy as it takes to save for 60 days ofhibernation” said Fenton. “White nose disrupts that schedule. Soinstead of waking up after 60 days they wake up two to three times aweek and they just burn themselves out usually by January. And thereis no recourse – they can't go out of the cave when they'rehibernating in the middle of winter and catch food. White nose thefungus is a symptom of what causes the problem. It's disruptinghibernation that matters.”

Despite research a solution for white nose syndrome has not yet been found.

“There's a lot of people concernedabout it but there doesn't seem to be any magic bullet” saidFenton.

There are things we can do for the batpopulation and one of those acts is to hang a bat house or bat boxon properties to help give bats a safe place to roost and hibernate.

Bat Box Building Workshops will be heldon Saturday June 9 at the HHOA Fish Hatchery and Saturday July 21at Abbey Gardens. Call 705-457-3700 to sign up or get on a waitinglist. A new HHLT publication Best Management Practices for Bats is available on the HHLT website at haliburtonlandtrust.ca.Information about the second year of the Bat Project is available atthe HHLT web site. Bat observations can be reported to ChristelFurniss at admin@haliburtonlandtrust.ca .