Connecting people with nature in Ontario's Mississippi Valley

The speaker shows her mussels at natural history talk, a report of the April 2013 MVFN lecture report by Jim Bendell

At a recent natural history lecture in Almonte, the Mississippi Valley Field Naturalists (MVFN) welcomed ‘malacologist’ Jacqueline Madill, Senior Research Assistant, Zoology, Research and Collections, Canadian Museum of Nature as guest speaker for the MVFN 2012-13 ‘Nature Beneath our Feet’ lectures. Madill’s subject was the important but little-understood or appreciated, ‘Native Fresh-water Mussels of the Ottawa Valley’ and she brought many several favourite specimens to the talk. About one-third of the worlds’ mussel species live in North America, with 55 species in Canada, of which 41 are found in Ontario. Madill reminded us first thing that we should not pick up mussels from the river bottom; each species inhabits only a specific water zone and they have limited locomotion. Not only that but freshwater mussels are considered one of the most endangered group of species in North America, with 67% at risk!

Mussels and Clams belong to the family Mollusca (derived from Latin: soft), a very large group of soft-bodied animals that also includes the Chitons, Tooth Shells, Snails and Slugs, Oysters, and the Nautili, Squids and Octopuses! Look them up and be amazed! In abundance and diversity, they are second only to the Arthropods (which includes Insects), and were among the first creatures on earth. Mussels and clams range in size from barely visible to approximately 20 cm in length. Both are bivalves living in a box of two shells. Think of the Blue Mussels or clam chowder you last ate at the fish restaurant, said Madill. Two limey (mainly calcium carbonate) shells enclose their ‘bivalve’ body in a box that may be opened or closed for passage of water, and protection. This structure reflects the life of a sedentary animal (or couch potato), no head or limbs but a muscular foot that provides anchorage and infrequent locomotion. About the body is a mantle that produces the shell and aids in growth and reproduction. Within the body there are various organs that work as in our own. Most important are the gut and gills that act in feeding, as part of a giant filter.

Madill and others assess Mussel biodiversity and numbers in local lakes and rivers as part of their work. Hinge structure and other features are used for identification and often identification can be made just by the feel of the shell underwater. Mussel species may vary in numbers from zero, to a few, to such an amazing density one cannot walk without treading on a shell. Here they earn the names ‘Heelsplitter’ and ‘Ouch’! Other more ‘happy as a Clam’ individuals are Rainbow, Warty Back and Maple Leaf. Eastern Elliptis is a very common species locally, and others such as a Cylindrical Papershell found in Quebec, had not been seen since the 1830’s.

Why mess with mussels? Well, we must agree that water is fundamental to life. Here in the Ottawa Valley we are well supplied with five major rivers and many smaller streams, and so should have abundant clean water and excellent aquatic life. But if we are to sustain and improve our standard of living we must care for our waters. And the study and care for Mussels and Clams are part of that concern because these little-known animals give many ecological benefits. Perhaps the most significant is their filtering; an individual may ingest and clean 3 liters of water per hour, removing toxic chemicals, excess nutrients, harmful bacteria and viruses, and importantly light blocking matter. They also provide benefit by mixing sediments as they slowly move. They provide food for fish, muskrats, shorebirds and others. Also since some mussels are quite long lived, many living decades, they carry within their tissues a useful record of biological and chemical changes in the environment. As they age annual rings form in the shell as in a tree. According to Madill, some Eastern Pondshells can live 200 years!

But why are Mussels so endangered? At one time, commercial harvest and disruption from log drives reduced their numbers, but these are not ongoing. Now the sermon; sadly, and to our peril, the current plight of bivalves reflects the damage we have done and are doing to water and its inhabitants. Mussels need clean, clear running water relatively high in oxygen and water bodies connected to maintain stable levels and flow, provide nutrients, and permit dispersal of the young. In turn, the density and persistence of these creatures are good indicators of healthy waters. Main disrupters are dams and locks that restrict flow and cause extreme fluctuation in temperature and levels of water. According to Madill, it can take 50-100 years for an area of mussels to be reestablished once it has been disrupted. Mussels are also particularly sensitive to pollutants of many kinds which include fertilizers from lawns and cropland. Many large water bodies and waterways have been made uninhabitable by channeling, loss of near shore habitat, and choking with litter and debris. Another significant threat has been the invasive Zebra Mussel, perhaps the most damaging to our native bivalves, as well as to human infrastructure such as intake pipes. It appeared in the Great Lakes in 1988 on ships from Middle Europe. Of incredible reproductive capacity, one female can produce 30,000 to 1,000,000 larvae annually. Madill noted that Mussels of the Rideau River have suffered a ‘double whammy’ from Zebra Mussels and the rapid and alternating water levels due to the canal locks. In 10 years Zebra Mussels have spread throughout the Great lakes smothering large beds of native bivalves.

Another issue raised by Madill’s was the intriguing connection between the decline of particular Mussel species and the decline of biodiversity in local fish. The explanation is as follows. Mussels and clams live partially buried in sediment with little traveling about, which potentially restricts their distribution. The problem is solved by some Mussel species which produce specialized larvae, called glochidia (from the Greek: pointed or hooked), that are shed in clouds, manage to attach to the gills of a particular species of host fish, and so are transported. They then drop off in new habitat suitable to both fish and Mussel. For example, the female Pocket-Book Mussel extends its mantle, the tip of which is shaped, marked and moves like a small fish. This attracts a desired larger fish for a lift. When the fish ‘takes the bait’ the Mussel ejects a puff of glochidia that attach to the gills, thus obtaining a convenient taxi for its young! Other species mimic a worm to attract a ‘ride’. Check out Youtube.com for videos of some of these creative mussel displays, says Madill.

What can we do to improve the health of our waters and native fresh-water Molluscs? How can we make a Mussel as “happy as Clam?” If you would like further information, please contact our speaker, she welcomes inquiries and can be contacted at the Canadian Nature Museum Research Building in Gatineau or via email An excellent reference guide to local Mussels is by J. Metcalfe-Smith, A. MacKenzie, I. Carmichael and D. McGoldrick, Photo Field Guide to the Freshwater Mussels of Ontario, 2005, published by the St. Thomas Field Naturalist Club. Other useful references for general information on the zoology and ecology of Mussels and Clams include on-line information on Mussels of Eastern Ontario at pinicola.ca and books by Clarke, A. H. 1981, The Fresh Water Molluscs of Canada. National Museum of Natural Sciences, National Museum of Canada, and T.I. Storer and R. L. Usinger, 1957, General Zoology, McGraw-Hill, Toronto.

 

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Jacqueline Madill (left) spoke about the important but little-understood or appreciated, ‘Native Freshwater Mussels of the Ottawa Valley’ and brought many of her favourite Mollusca specimens to the talk, such as the Eastern Elliptio, a very common freshwater Mussel. Photo Pauline Donaldson

 

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‘Ground beetles’, a spectacular insect group, featured at MVFN natural history talk

Report of October 2012 MVFN Lecture

by Joel Byrne

About 350,000 species of beetles occupy this planet. They are found in nearly every terrestrial habitat and many watery ones, pole to pole. There are more named species of beetles than there are named species of any other group. When I saw the title of Dr. Henri Goulet’s presentation to the Mississippi Valley Field Naturalists: My Favourite Insect Group – Ground Beetles (Carabidae), I thought of a quote attributed to J.B.S. Haldane, a distinguished British biologist, who, when asked what he had learned about the ‘creator’ from looking at nature, replied that the creator “. . . has an inordinate fondness for beetles,” referring to the enormous abundance of beetle species. Henri Goulet, MVFN’s second speaker, in the lecture series Nature Beneath Our Feet, is a research scientist emeritus with Agriculture and Agri-Food Canada, and he also has a fondness for beetles—ground beetles. Why, out of 160 families of beetles would he choose to study ground beetles? The answer was found in his talk, as he shared some of his fond memories in a lifetime of adventures tracking down his favourite group of animals.

Henri (he is a friend) opened his talk by posing some basic questions: what is a beetle, what is a ground beetle? A series of photos outstanding for their clarity, detail, and colour followed, displaying anatomical features of beetles that distinguish them from other insect Orders. One could clearly see that the beetles have no tail-like structure and that their wing covers do not overlap. It is these wing covers or elytra which give rise to the name of the Order of insects to which beetles belong, i.e. Coleoptera, meaning ‘sheath wings’ in Greek. In this Order is a suborder, Adephaga, meaning ‘voracious.’ And in this voracious group is the ground beetle family, Carabidae, our speaker’s favourite.

Carabid beetles number some 1700 species strong in North America; 250 species around Ottawa. The carabids have long antennae, large jaws, and long legs. Some are very fast, among the fastest animals in the world, for their size. Combine their murderous mandibles with their long speedy legs and you have a formidable predator. Even their larvae are usually big-jawed, active insect predators. All this is bad for their prey, often invertebrates, and good for us since a lot of invertebrates we consider farm and garden pests, aphids, slugs and caterpillars, are consumed. If any invertebrate wishes to avoid being devoured by a ground beetle in Canada, they should retire to a cave, since this is one of the few habitats ground beetles don’t inhabit, we learned.

Then came the big question, posed by Henri—Why do I find ground beetles fascinating? Henri’s fascination and fondness for ground beetles goes back to his childhood days in winters when he dug down in snow, then into and under the leaves where he found many of his pals stiff with cold, and warmed them up. But what got Henri interested initially in studying ground beetles was seeing species with dark metallic reflections.

There are many other reasons ground beetles became so fascinating to Henri. Unlike butterflies and dragonflies which quickly fly away, adult ground beetles are easy to pick up under debris or under the soil surface. The adults are quite easily seen, ranging in size from 1.5 mm to 30 mm, most being 5-10 mm in size. Adults live at least one season and of course, can be found even under snow. Adults come in a great variety of shapes. Many shiny black ground beetles have a ‘typical’ shape, athletic, but some are anything but typical. The ‘snail eater’ is a case in point having ‘strikingly elongated mouth parts’ the better to lunch on the inside of a snail’s shell. There are round sand beetles that look like pills. Bombardier beetles are much wider aft than most, perhaps to house a sort of two-chambered gun at the end of their abdomen where they mix hot chemical ‘bullets’ and ‘fire’ them with an audible pop at anything that threatens them. Many in the Adephaga suborder are ‘accomplished stinkers’, thus avoiding predation.

Henri then showed us phenomenal photos of what, I believe, fascinated us all the most— their great variety of colours. The wing-cover slides alone, entitled Elytral Sculpture, were worth the price of admission. “Our perception is very much affected by what we are.” We are humans and most of us are more interested in butterflies than a lot of black beetles because as humans we are attracted to colours. So when the first slide of elytral sculpture popped onto the screen there was a collective sigh. Mind-bogglingly beautiful metallic greens, bronzes, purples and blue blacks, more emerald greens. Also turquoise wing covers trimmed with copper called ‘the best’ in Canada, Carabus vietinghoffi, from the land of small willows. It was as if a sculptor and a jewelry designer had collaborated in crafting them.

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As if an expert sculptor and jeweler had collaborated to craft it! A Carabus vietinghoffi, from the ‘land of small willows,’ with its turquoise wing covers trimmed with copper. This is the ground beetle Henri considered ‘the best’ in Canada. Photo Henri Goulet.

 

There followed a series of photos of completely-assembled, i.e. entire specimens of ground beetles, starting with solely black species, then switching to beetles ranging from pale to dark single-coloured, to two-coloured species, and then three-coloured species. Then came the ones with dark metallic reflections, the ones that initially interested Henri, then ones with bright metallic reflections (my favourites), and then species with two and three hues of metallic reflections, and finally species with metallic hue and pigment colours. At which point Henri said, “So I hope I’ve exposed you to a lot of colours.” We were mesmerized, colour-saturated!

 

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This ground beetle, Elaphrus clairvillei, inhabits only marshy meadows and swampy places. Dr. Goulet is an excellent photographer and here, as in many photographs, he has captured the stunning beauty of the beetle. Photo courtesy Henri Goulet.

The balance of the talk was devoted to many other special features of ground beetles which could have been a talk in itself. Most ground beetles hide in the day. Look for them under logs and rocks, and in stumps. Ground beetles are found on all land habitats except in water (one species stays under rocks submerged by tides). Most species are potentially excellent bio-indicators because their habitat requirement varies from quite narrow to extremely narrow. For example Elaphrus clairvillei inhabits marshy meadows and swampy places, but will not live in bogs as they are too acidic. Some adult ground beetles are very long-lived, 2-7 years. Most ground beetles are finicky about where they live but not fussy about what they eat. A good example, ‘caterpillar hunters’ (Calasoma sycophanta), are forest ground beetles which emerge in the spring, look around for their prey and venture out and stay out if their prey is present, otherwise they return to the ground. Among ground beetles there are predators, scavengers, and herbivores (many are ‘weed-seed’ eaters), and even parasites (the very colourful leaf beetle parasites for example)—a very wide range of modes of life indeed.

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A huge fan of the ‘ground’ beetles, Dr. Henri Goulet (centre), fields questions after his talk at the Almonte United Church, while others examine some of the many species specimens provided by the speaker for display. Photo Pauline Donaldson

The talk wound down with a lively question and answer period, while in the background the slide show continued. There was an initial burst of oohs! and ahs! as very colourful beetles seemed to dash across the screen: fabulous close-ups of live tiger beetles on the hunt. What a spectacular way to end the show!

A word about Henri Goulet’s photographs— superb! His photos, taken with meticulous care, will long be remembered by those who set aside a few hours of a fall evening to learn and be entertained by the learning. What I came away with was the impression of incredible beauty in the colours and design of the host of ground beetles, each species with its own variation on the general plan.

I enjoyed the lecture so much I saw it twice!

Resources: reference books on ground beetles are Common Ground Beetles (1987) by Trevor G. Forsyth and An Illustrated Identification Guide to Adults and Larvae of Northeastern North America Ground Beetles (2010) by Yves Bousquet.

 

 

 

 

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May 2012

“World of Woodpeckers” presented by Dan Schneider, Senior Interpreter, Grand River Conservation Authority

Woodpeckers superbly adapted insect hunters and wood home builders: a lecture report by Eugene Fytche

The Mississippi Valley Field Naturalists (MVFN) 2011-12 natural history lecture series continued recently in Almonte. Members of the Mississippi Valley Field Naturalists (MVFN) and the public enjoyed a rare insight into the “World of Woodpeckers” during a presentation at MVFN’s Annual Spring Gathering Banquet and AGM. The guest speaker was Dan Schneider, Senior Interpreter of the Grand River Conservation Authority. Although describing himself as a generalist, Schneider revealed a profound knowledge of woodpeckers, and kept his audience fascinated by his description of the variety of species of the woodpecker family (Picidae) and their remarkable adaptations. “Woodpeckers are best at exploiting the surface of trees. If you are an insect, you cannot hide from them!” said Schneider.

A map of the global distribution of the over 300 species of woodpeckers showed that there are species on all continents with the exception of Australia including New Zealand. By some quirk of nature, although they are found in Africa, there are none on the Island of Madagascar. The family is divided into four main groups: the piculets, found mainly in the tropical regions, the wrynecks found mainly in Africa (with the peculiar characteristic that they, like owls, can turn their head through nearly 180 degrees), and the sapsuckers in North America, along with woodpeckers as we know them. Nine species of woodpecker are found in Ontario. Most have a peculiar ‘zygodactyl’ arrangement of toes (with sharp, curved claws), two forward and two back (on each foot) so that they can grip the trunk of a tree while bracing themselves with specialized stiff tail feathers. Although Mr. Schneider digressed to tell us some interesting traits of the other groups, he sensed that his listeners were most interested in his insights into the North American birds, and produced many superb slides of both the better known species and species unfamiliar to the audience.

He explained that, of the largest woodpeckers ever found in North American, the Imperial Woodpecker and the Ivory Billed Woodpecker are now extinct (although there are extremely rare US sightings of the Ivory Billed). So a familiar local bird, the Pileated Woodpecker, now has the distinction of being the largest of our woodpeckers, and sightings and its distinctive loud repetitive calls are frequently enjoyed here.

The Pileated (or crested) Woodpecker might also be called the Condominium Developer of the Woods. It creates prodigious holes in both live and dead trees, and is a cavity nester, needing a cavity two feet deep (which can take up to a month to excavate), usually in dead tree stumps, to lay its eggs and raise its young. Its cavities throughout the forest become home to a wide range of plants and animals. The Wood Duck and the Flying Squirrels are frequent tenants. As food for humans, Audubon reported, that the Pileated Woodpecker tasted “bad”! First Nations people in America hunted the birds for food and used the crest feathers for decoration.

The most common local species of woodpeckers, the Downy Woodpecker and the Hairy Woodpecker, are hard to tell apart when seen separately; when together there is no problem since the Hairy Woodpecker is twice the size of the Downy which is about the size of a Chickadee. One thing to remember is that the smaller Downy has a small nail-sized bill. Other characteristics by which we can distinguish them: the Downy has black bars on its tail, and the male has a red spot on the back of its head. The Hairy has a much bigger beak, white outer tail feathers and the male has a red spot on his head. Both range from the Gulf of Mexico to Northern Canada. They feed on insects that they can hear in the tree trunks, but are partial to suet and sunflower seeds from feeders.

The impact of the straight bills of woodpeckers striking sound wood is of the order of 1200 g’s, and the birds’ well-being is dependent on hitting the wood straight on. Otherwise the physical defense against the impact, given by the peculiar arrangement of cushioning muscles, would not be effective. The brain in particular is well cushioned by muscles against the shocks. The ‘tool’ used by woodpeckers for extracting the ants, worms and insects that they hear in the trees is an extremely long tongue stored back over the skull and anchored behind the nostril. This amazing arrangement is unique to woodpeckers.

Northern Flickers on the other hand do not have straight bills, and tend to feed on ants on the ground. There are several morphs, all having long sticky tongues used to trap the ants. One flicker was found with over 5000 ants in its stomach. Schneider said they are so specialized that they really are filling the ecological niche of an anteater. They also catch insects in the air, eat fruit, and will visit feeders.

Another type of woodpecker, the Sapsucker, drills parallel lines of holes in trees to drink sap, but also catches insects in the air or on the ground. They are also cavity nesters. The drilling of trees, especially sugar maple, causes wells of sap in spring and provides a sugary food essential to hummingbirds and other animals when none else is available. Yellow-Bellied Sapsuckers found in Ontario are an important bird. Schneider considers them a ‘double keystone species.’ A keystone species is one whose existence makes it possible for other species to inhabit an area. The Yellow-Bellied Sapsucker can be considered a double keystone species because not only does it make cavities in trees creating habitat for other species, but the sap wells it makes provide essential food for hummingbirds and others.

Schneider described other species of woodpecker, including the ones with three toes instead of four, and obviously would have broadened our knowledge much further if time permitted. However, he had run out of time. He did mention that, interestingly, one of the three-toed woodpeckers, i.e. the Black-Backed Woodpecker is usually very unafraid of people. It favors burnt out areas of the forest. The American Three-Toed Woodpecker is the other three-toed woodpecker in Ontario. The well-named Red-Headed Woodpecker is rarer in the past 20 years during which a 60% decline has been noted. The last of the nine Ontario species mentioned, the poorly named Red-Bellied Woodpecker, Schneider noted, seems to be moving north, presumably as the climate warms.

Our speaker subsequently responded to a number of questions, among them “Why do woodpeckers peck on steel roofs.” The answer: to make more noise, marking territory and attracting a mate. Schneider was given a rousing round of applause by the audience.

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Following a short Annual General Meeting and fabulous buffet dinner prepared by Almonte Civitan Club volunteers, the audience sits back to enjoy Dan Schneider’s World of Woodpeckers presentation. Photo Pauline Donaldson

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Earlier in the evening, Al Potvin had been presented with an MVFN Champion for Nature Award for his role in the production of a large number of bluebird boxes for MVFN’s habitat creation program. Speaker Dan Schneider referred to this during his woodpecker presentation, stating that Al, in making the boxes, occupied the ecological niche of a woodpecker! Photo Pauline Donaldson

 

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Keystone Inhabitants of Streams and Forests

by Fred Schueler

Bishops Mills Natural History Centre

RR#2 Bishops Mills, Ontario, Canada K0G 1T0

(613)258-3107 <> http://pinicola.ca/

Report of the talk “Salamanders: Unseen, Unheard, but NOT Unimportant” which was to have been given by Mike Oldham to the Mississippi Valley Field Naturalists (MVFN), 26 January 2012; the 4th lecture in MVFN’s 2011-2012 natural history lecture series: Trends in Flora and Fauna. The report was written by local naturalist Fred Schueler, who was to write this report and thank the speaker, but who also delivered the talk when Mike was prevented by weather from reaching Almonte, after Cathy Keddy reconstructed Mike’s presentation from e-mailed files.

Blue-spotted Salamander Ambystoma laterale (upper photo courtesy Cathy Keddy) is the most frequently encountered species in our area, often wandering into basements or garages, or turned up under wood; the red colour of the terrrestrial stage of the red-spotted newt serves as a warning to predators that the eft is poisonous. Efts such as this one photographed during MVFN’s 2010 bioblitz near Almonte are the only salamanders you’ll see wandering aaround in daylight (lower photo courtesy Karen Thomson)

On 19 Jan 2012 3:26 PM, Oldham, Michael (MNR) wrote:

> I ended up turning around and heading home, so won’t be at this evening’s MVFN meeting this evening. So sorry… It is still snowing very heavily here with lots of accumulation… I just got home and driving back from where I called, between Norwood and Havelock, was even worse than the drive there. Blowing snow, freezing rain, poor visibility, slow snow plows with impatient drivers and truckers trying to pass, slippery roads, snow squall warning in effect, cars in the ditch, and the MNR minivan I was driving is not very good in slippery conditions. I was averaging 40-50 km/hr, often slower in long stretches behind snow plows or sanding trucks, half the speed under normal conditions, so my estimated 3 hr drive would have been 6 hrs, unless conditions improved. I hope the snow squalls abate before they reach your area and affect people travelling to and from Almonte.

I was setting out to drive the Dwyer Hill Road to Almonte when the wife banged on the van window to announce she’d just read Mike’s e-mail, but I was soon setting out again with the plan that I would give Mike’s talk from his e-mailed presentation. All the way up the Dywer Hill Road there was no snow at all, though things were blizzard-like soon after I reached Almonte.

I began the lecture by introducing Mike Oldham, herpetologist and botanist at the Natural Heritage Information Centre (NHIC, Ontario Ministry of Natural Resources) in Peterborough, co-founder, in 1984, of Ontario’s Herpetofaunal Summary, the first modern atlas of “reptiles” and Amphibians, and the person you turn to when you need a copy of any paper relevant to Ontario natural history (and often he’s sent it to you before you ask). I illustrated his scope as a field naturalist from the top of my e-mail SENT box – correspondence about introduced Xerolenta snails and Dyssodia Dogweeds along Ottawa highways, freshwater mussels he’d collected all across southern Ontario, a new book about European Sedges, and the status of invasive Cattails in Ontario…

So Mike is known for his interest in spectacular but inconspicuous creatures, and Salamanders are leading members of this group. This report is compounded of his notes, and my local knowledge of Salamanders in Eastern Ontario.

Salamanders retain the long-tailed, four-limbed shape of primitive land-dwelling Vertebrates, overlaid by a wide range of specialized adaptations. They diverged from the tailless Frogs some time before the earliest known Salamander fossils, from the Middle Jurassic, 164 million years ago. There are now about 550 species of Salamanders in the world. Among provinces, Ontario has the greatest number of species, probably because it is closest to the southern Appalachian region, which is the world centre of Salamander diversity. Our Salamanders range from 35 mm to almost half a metre in length, and show remarkable variation in life histories and habits. Some spend their entire lives in the water, others live on the land but breed aquatically, and some have an entirely terrestrial existence. Salamanders may breathe via gills, lungs, and skin, or can be lungless and breathe only through their skin. Moisture is thus a very important factor regulating their distribution, and they tend to be active on the surface mostly on rainy nights, when potential observers tend to seek shelter.

Salamanders are elusive, and in addition to being rarely seen at the best of times, and on the formerly ploughed and trampled lands of eastern Ontario, they’re often much rarer than they were before settlement, though because of their effectiveness as predators they are often regarded as “keystone predators” in intact forest ecosystems of eastern North America.

Thirteen species of salamanders are known from Ontario, including six that are legally listed as “at risk” either federally or provincially: none of these, and all of the others, occur in eastern Ontario. The “at risk” species fall into 2 groups, stream salamanders of the Niagara Peninsula, and hybridizing Ambystoma Mole Salamanders of southwestern Ontario.

There is only a single confirmed record of the Eastern Tiger Salamander (Ambystoma tigrinum), from Point Pelee in 1915. The Jefferson Salamander (A. jeffersonianum), is similar to, and hybridizes with the widespread Blue-spotted Salamander, but it is restricted to scattered sites around the southern Niagara Escarpment, the Greater Toronto and Golden Horseshoe areas, and is generally threatened by destruction of its habitat. The Small-mouth Salamander (A. texanum), is restricted in Canada to Pelee Island, and also part of the hybridizing complex there.

There are two species of Dusky Salamanders, genus Desmognathus, in Ontario, both restricted to the Niagara River Gorge. For decades there’d been attempts to replicate an old record from “across from Buffalo,” but in 1989 James Kamstra and Wayne Weller found Dusky Salamanders in two small streams in the Niagara Gorge, and it turned out that one of these populations was D. fuscus, the Northern Dusky, and the other D. ochrophaeus, the Allegheny Mountain Dusky. We can see the habitat of both of these species, in New York across the St Lawrence River from eastern Ontario, but they never made it across the St Lawrence lowlands to Ontario. Another Stream Salamander species, the Spring Salamander (Gyrinophilus porphyriticus) is known only from three Niagara Peninsula larvae collected in 1877. There is also an old larva of this species supposedly from Britannia, in Ottawa, but decades searching hasn’t turned up a population here.

Eastern Ontario is not a particularly diverse area for salamanders, but the seven species found here have a variety of different life histories and are among our most poorly known Vertebrates.

The Mudpuppy (Necturus maculosus) is Ontario’s largest salamander, reaching a foot or more in total length. These salamanders are permanently aquatic and have feathery gills behind the head, and other features of the larval morphology that other species lose when they mature. Mudpuppies occur in larger rivers and lakes throughout southern Ontario, as far north as Thunder Bay and the upper Ottawa River, though their distribution is poorly known due to their permanently aquatic habits. They’re known from the Rideau, Mississippi, and Madawaska rivers, on the basis of only a few records. The one place they can be easily seen in eastern Ontario is during the winter at Mudpuppy Night in Oxford Mills – http://pinicola.ca/mudpup1.htm – where many Mudpuppies from an abundant population are out in the open during their winter activity period.

The Salamanders with the least surprising life history are the Ambystoma “Mole Salamanders,” so called because they spend much of their lives underground – like frogs these live on land and come to ponds to lay eggs in the spring, which hatch into larvae which, like tadpoles, transform to leave the water to live on land until they come back to breed in ponds as adults.

The Blue-spotted Salamander (A. laterale) is the most frequently encountered species in our area, often wandering into basements or garages, or turned up under wood that has been resting on the ground. Adults are about 13 cm in total length; they are black or dark brown with variable amounts of bluish spots or flecks. This species is closely related to the Jefferson Salamander, which does not occur in eastern Ontario, and the two species hybridized historically to produce unisexual polyploids which contain multiple sets of chromosomes from both the Jefferson and Blue-spotted Salamanders and are almost indistinguishable from the parental species except through genetic testing. These polyploid populations are almost entirely female and usually must mate with a male of one of the parental species to reproduce, though usually rejecting the chromosomes from his sperm. There are also situations, especially in disturbed habitats, where the sperm is incorporated and the number of sets of chromosomes increases as high as seven; these hybrids have the chromosomes of their “parent” species, but the cytoplasm of a southern species which does not occur in Canada; much of the research on these hybrids has been done by Dr. James Bogart and students at the University of Guelph.

At one time the polyploids occurring in eastern Ontario were called a separate species, Tremblay’s Salamander, larger and less spotted than ordinary Blue-spots, with two sets of Blue-spotted genes and one of Jefferson genes; but since it doesn’t reproduce sexually it is no longer considered a separate species.

Our other Ambystoma is the Yellow-spotted Salamander (A. maculatum). This large, blackish Salamander has two rows of large yellow spots on its head and along its back and tail. It can grow to over 20 cm in length. It’s fairly common on the Shield, including Lanark County, but is restricted to mature woods on sandy dunes in the limestone country of easternmost Ontario. The large, slow-hatching, jelly-swathed egg masses are conspicuous in woodland breeding ponds in the early spring.

The Eastern or Red-spotted Newt (Notopthalamus viridescens) has a life-cycle that differs from any other Ontario salamander – the larvae transform into a terrestrial stage known as the “red eft” and spend 2-4 years on land in the woods. They then return to the water to become mature aquatic adults. Adults have expanded tail fins, and are dark above, often a greenish-brown colour, with prominent black-ringed red spots on their sides; efts are orange-red, with the same red spots, but narrow tails. The red colour serves as a warning to predators that the eft is poisonous, and efts are the only Salamanders you’ll see wandering around in daylight. In eastern Ontario the distribution of Newts is very scattered, and they may be declining.

The final, and largest family of Salamanders is the lungless Plethodontidae. We have two specialized uncommon species, and one that is widespread and relatively abundant.

The species with the most specialized habitat is the Four-toed Salamander (Hemidactylium scutatum). In May the females leave their woodland habitat and form cavities in moss, typically Sphagnum, overhanging water, where they lay their eggs. When the larvae hatch they wriggle down through the moss into the water where they live until they transform. Although the Four-toed Salamander has only four toes on its hind feet while similar Salamanders have five, the tiny toes are not a particularly useful identification character – better are the constriction at the base of the tail and the underside which is bright white with bold black spots, quite unlike the greyish underside of the Red-backed Salamander, with which it could be confused. Undoubtedly the species is more common in eastern Ontario than very few old records indicate – you have to go to bogs or other moss-banked ponds or ditches during the breeding season to have the best chance of finding them.

Another small, slender Plethodontid Salamander is the Two-lined Salamander, Eurycea bislineata, almost always found in or very near running water or gravelly seepages. This species is generally gold-coloured with two dark longitudinal stripes down its back. Eggs are laid beneath flat rocks in streams and the larvae live in the stream until they metamorphose. The best way to find them is to flip over rocks just at the edge of a stream or lake. Two-lined Salamanders are not found in southwestern Ontario, but are locally common in a band from Georgian Bay, across Algonquin Park to Quebec, and south to the St. Lawrence River, though they are found east of the Shield in Ontario only in a very few sites where water flows into streams through seepages of clean gravel. Lanark County is part of this range where the species is fairly common; there used to be a population below the dams in Almonte, but the new hydro station has been built over the site where they occurred.

The Eastern Redback Salamander, Plethodon cinereus, is usually regarded as the most abundant Vertebrate in the forests of northeastern North America. These Salamanders act as keystone predators to regulate the invertebrates of the forest floor community, and through them the character of leaf litter decomposition, soil, and nutrient cycling in the forest. Red-backed Salamanders are an exception to the rule that our Amphibians lay their eggs in water, since they lay their eggs in moist spots inside or beneath rotten logs and the entire larval stage of the salamander occurs inside the egg, as they are attended by the mother.

The Small Eastern Plethodon Salamanders, like several other of the common Vertebrates in our forests (Ruffed Grouse, Screech Owls, and Redbelly Snakes), have distinct reddish and greyish colour forms. Rufous and ashy are plausible colours for cryptic forest creatures, as the colours of freshly dead and decayed leaves, and they are produced by the different hues of the melanin pigments – phaeomelanins producing reds and eumelanin grey or black. In Plethodon these morphs are ‘leadback’ – unpatterned and charcoal gray, and ‘redback’ with a reddish dorsal stripe. In New England leadbacks are more frequent in warmer localities, and it has been found that the morphs forage at different temperatures, with a corresponding difference in basal metabolic rates. Across most of southern Ontario populations are mixed, with leadbacks rarely frequent, but in eastern Ontario south of Ottawa and east of the Frontenac Axis there are no redbacks. Reasons for this monomorphic region, or genetic differences between the populations, have not been studied.

Pleistocene ice sheets wiped out any native Earthworms that had lived in Canada, leaving North American species, in the family Megascolecidae, only where glaciation was incomplete, on Vancouver Island and the Richardson Mountains of the Yukon. The 25 or so European species that now live in Canada, in the family Lumbricidae, are thought to have come in the rootstocks of plants imported by settlers or in soil used for ballast in ships. Nowadays, in many Ontario forests, last year’s leaves seems to be all there are…. the rest have been pulled underground and consumed by Earthworms, and increasingly many naturalists have noticed that Earthworms are changing the ecology of forest floors, first in urban parks and now even in protected old growth forests. The missing leaf litter was home to complex communities of everything from snails to Nematodes to Springtails to Centipedes to Beetles to Salamanders, and to the extent that their habitat is gone, the fauna must be gone from the forests with minimal leaf litter. The invasion of wooded areas by non-native Earthworms can also lead to the decline in some native plants, such as rare woodland Orchids that depend on a rich humus layer, as well as facilitating the invasion of wooded areas by non-native plants.

In 2006 James Gibbs and Nancy Karraker found that the frequency of leadbacks had increased with, but faster than, increasing temperature over the course of the 20th century. It’s possible that the excess increase in the leadback morph, above that predicted by climatic warming, may be due to the effects of Earthworms in warming the soil, and in 2010 at the Shaw Woods in Renfrew County this result was found in an Earthworm-ravaged, but otherwise protected, oldgrowth woods, where reduction in litter depth by Earthworms is the main observed longterm disturbance.

 

Top: Joe Crowley’s photo of a redback (Plethodon cinereus) on Earthworm castings. Bottom: Bev Wigney’s photo of a leadback Plethodon, also on Earthworm castings.

The first way to contribute to our knowledge of Salamanders is through Ontario Amphibian & Reptile Atlas – once you get out into habitat and ‘turn cover’ to discover these creatures, you can report your records online – http://www.ontarionature.org/protect/species/herpetofaunal_atlas.php – or you can co-operate with our effort to resample places where Plethodon have been collected in the past – http://pinicola.ca/thirty/pcin_2012.htm – to see if abundance or colour morph ratio of this species have changed in recent decades.

author’s contact information: Fred Schueler

Bishops Mills Natural History Centre

RR#2 Bishops Mills, Ontario, Canada K0G 1T0

(613)258-3107 <> http://pinicola.ca/

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Flying Squirrels—Nocturnal Aviators

Upcoming MVFN Lecture: Thursday, November 17, 2011

 The Mississippi Valley Field Naturalists’ (MVFN) public lecture series, Trends in Fauna and Flora, continues November 17 with the third presentation, “Flying Squirrels—Nocturnal Aviators.” You do not need to be an expert to enjoy the presentations—just possess a curiosity or appreciation for wild nature. Cottagers, hunters, fishermen, canoeists, hikers, campers, artists and seasoned field naturalists alike will find something to interest them as we explore what lives in Lanark County and how best to protect it for future generations. Refreshments are offered at each lecture.

 This month’s lecture will be presented by Dr. Jeff Bowman from the Ontario Ministry of Natural Resources and also an adjunct professor at Trent University. He has studied flying squirrel ecology in Ontario for years, looking at genetics, habitats, boundary dynamics, population density, and landscape patchworks. Dr. Bowman’s presentation will give us an opportunity to become familiar with these rarely seen relatives of the familiar chipmunk, red squirrel, and grey squirrel.

 There are over 40 species of flying squirrels in the world, including the Asian giant flying squirrels, woolly flying squirrels (Pakistan), Winston Churchill’s flying squirrel (Sumatra), dwarf and hairy-footed flying squirrels (southeast Asia), complex-toothed flying squirrel (China), and pygmy flying squirrels (Malaysia). Just two species are found in North America—the northern and southern flying squirrel. Both species are thought to have migrated to our continent across the Bering land bridge, but at different times. The evidence lies in the nature of the baculum (a small bone that supports the penis and facilitates mating). The baculum of the northern flying squirrel is structurally much closer to that of an Asian genus of flying squirrels than to that of the southern flying squirrel.

 Northern flying squirrels typically are found in coniferous or mixed forests, while the southern flying squirrel occurs in deciduous and mixed forests. Both species rely on cavities in large trees and are sensitive to forest fragmentation. Thus they are used as indicator species of forest habitat quality in many regions of North America.

 Lanark County is home to both kinds of flying squirrels, which are active only at night. Have you ever seen a flying squirrel? In the winter months, I often see them at my bird feeder. A violently-rocking feeder on a still winter night is the tip-off. Closer inspection reveals a pair of flying squirrels which appear to be in constant motion, darting from tree to feeder and back again, their large eyes glowing in the house lights.

 So how can you tell these two squirrels apart? Southern individuals have a smaller body size than a chipmunk, while the northern ones are larger than this striped relative. Southern flying squirrels (20 to 25 cm long) have grey brown fur on top with darker flanks and are a cream color underneath. Northern flying squirrels (25 to 37 cm long) have light brown or cinnamon fur above with greyish flanks and are whitish underneath. Still not sure? Come to the lecture and see them up close.

Flying squirrels are fascinating. Depending on the wind and takeoff height, they can glide for 50 metres or more. A skin membrane, called the patagium, is stretched between their relatively long front and rear legs, allowing them to sail from tree to tree. While airborne, they can change direction with the use of their long, flat tail. These arboreal squirrels have sharp, curved claws and hind feet that can rotate 180 degrees while descending a tree. Their large eyes and long whiskers are typical of nocturnal mammals. Flying squirrels often share nests. While a nest typically houses 2-5 individuals, over 50 have been found co-habiting! Nest-sharing is important for conserving energy and maintaining body temperature in the winter, as flying squirrels do not hibernate.

Many species have responded to modern climate change through shifts in their geographic range. A recent study showed that southern flying squirrels in Ontario rapidly expanded their northern range limit in response to warmer winters. This resulted in more overlap with the range of the northern flying squirrel. Not only that, but where they co-occurred, the species interbred and created fertile offspring! This was the first report of hybridization between North American flying squirrel species.

 Go squirrelly and learn more about the habits, habitats, and conservation of these dynamic, flightly small mammals. Ponder their response to climate change at Dr. Bowman’s presentation “Flying Squirrels—Nocturnal Aviators” at 7:30p.m. on Thurs. Nov. 17, 2011, Almonte United Church, 106 Elgin St., Almonte. All are welcome ($5 fee for non-members). For further information please contact MVFN’s Program Chair, Cathy Keddy at 631-257-3089.

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