Category Archives: Amphibians

Ecologically Yours

By Art Goldsmith

August 19, 2015

Another fine summer day in August found me in the company of Grégory Bulté and his Ecology Field Course. Grégory is an instructor at Carleton University’s Biology Department, and according to the university’s website, he is:

“…broadly interested in the ecology, evolution and conservation of animals.”

What this does not tell you is that Grégory’s enthusiasm and knowledge about the life around Lake Opinicon and the wetlands bordering the lake, are boundless.

Officially the course is called “Field Ecology & Natural History” and this year was offered to 12 students during the last two weeks of August at QUBS.

Grégory, with his blue t-shirt in the foreground, here supervises the survey of some of the animals that live along the shores of Lake Opinicon, some rarely being seen at all. The purpose of this field study is to learn about the diversity of the lake and surrounding lands.

Grég raises the trap. The mysteries of the lake are revealed

Turtles, fish, frogs and snakes are briefly captured, photographed, identified and then released. Lake Opinicon is home to some less common turtles, like the Northern Map Turtle (Graptemys geographica) and the Eastern Musk Turtle (Sternotherus odoratus). Note the excellent Latin species names, “geographica” and “odoratus”. They are both so descriptive of the animals. Map Turtles are named for the markings on their shells, which are reminiscent of the lines of a topographical map. Musk Turtles are also called Stinkpots, because they emit a stinky liquid from their musk glands when disturbed.

A Northern Map Turtle swims for the camera. (Photo by Grégory Bulté)
A Northern Map Turtle swims for the camera. (Photo by Grégory Bulté)

Below is a photo by your blogger of a very shy Musk Turtle taken at Lake Opinicon a few years ago. It is rare to see one out of the water. They do, on occasion, emerge onto a snag that angles out of the water, like this one, usually in an area that is well hidden. These are small turtles, usually less than 13 centimetres long. Map Turtles are among our larger turtles. Females in Lake Opinicon have measured up to 26.5 cms long and males up to half of that length. They are often seen basking on larger rocks in our rivers and lakes in Eastern Ontario.

Musk Turtle

This photo of Grég tells us about the joy of the field course. It captures the underlying good feelings from learning in the field. The photos that follow were all taken by or provided by Grég.
This photo of Grég tells us about the joy of the field course. It captures the underlying good feelings from learning in the field. The photos that follow were all taken by or provided by Grég.
The lake, the sky and the clouds dwarf the class as they check a trap. Many fish were in this trap. The majority are sunfish, mainly Bluegills and Pumpkinseeds (Lepomis spp.)
The lake, the sky and the clouds dwarf the class as they check a trap.
Many fish were in this trap. The majority are sunfish, mainly Bluegills and Pumpkinseeds (Lepomis spp.)
Many fish were in this trap. The majority are sunfish, mainly Bluegills and Pumpkinseeds (Lepomis spp.)
Every grade-school kid's first ecology lesson... big fish eat little fish, in this case, a fingerling Bass is swallowing a neighbour not that much smaller than the Bass.
Every grade-school kid’s first ecology lesson… big fish eat little fish, in this case, a fingerling Bass is swallowing a neighbour not that much smaller than the Bass.

Blackchin Shiner

Two of the many representatives of the Cyprinidae family (minnows and carp) in Lake Opinicon. Above is the Blackchin Shiner (Notropis heterodon) and below is the Golden Shiner (Notemigonus crysoleucas).  The Blackchin Shiner is native to the Great Lakes‒St. Lawrence basin. It is a small fish, rarely exceeding 6 cms.  The Golden Shiner may grow up to 30 cms., although most are in the size range pictured below.  This popular bait fish is native to much of eastern and central North America and has been accidentally introduced well beyond its native range.

Golden Shiner

Frogs abound in and around the lake.  The first two photos, above, feature a frog that rarely leaves the water, the American Bullfrog (Lithobates catesbeianus). Our largest frog in Ontario, the Bullfrog is very aggressive with other frogs—and anything else that moves!  The third photo, above right, is a Green Frog (Lithobates clamitans). This is also a large, mostly aquatic frog, which is frequently mistaken for the Bullfrog. Note the clearly visible ridges running down the sides of this frog’s back.  These ridges are distinguishing marks of the Green Frog. Below left is a photo of a Leopard Frog (Lithobates pipiens). Leopard Frogs travel far from the water during the summer months and return to overwinter in lakes and ponds. Below top centre is a Wood Frog (Lithobates sylvaticus), distinguished by facial side masks. Scrunched up on the Milkweed leaf, below right, is a Grey Tree Frog (Hyla versicolor), our loud summer frog. Its call is often mistaken for a bird. As the Latin name suggests, the Grey Tree Frog changes colour to match its surroundings for better camouflage. The Green Frog and Leopard Frog photos were taken by Art Goldsmith. The remaining four photos were taken by  Grégory Bulté.


The other group of common, and usually hidden, amphibians is the salamander (above lower row).  The three species above are best seen in early spring when spring melt waters and warm rains form ponds and pools where many salamanders breed in the evening hours. These salamanders spend most of their time dug into the soil or beneath rocks and fallen tree limbs in moist forests where they hunt for invertebrates. The three of Ontario’s 12 species shown here are, from left, Blue-spotted (Ambystoma laterale), Spotted (Ambystoma maculatum), and the lung-less Eastern Red-back (Plethodon cinereus). The latter is a member of the Plethodontidae family.  The species in this family have no lungs, and therefore are restricted to moist, terrestrial habitats where they breed and lay their eggs.  The other two Ontario members of this family are the Two-Lined and the Dusky Salamanders, neither of which have been recorded at QUBS.


For a slight change of focus, we look at a few reptiles.  Above are two photos of a Northern Water Snake (Nerodia sipedon sipedon) that posed for students.  This common reptile is found in and around ponds, lakes and rivers throughout the southeastern portion of Ontario.  Below is a much rarer species, the Eastern or Grey Ratsnake (Pantherophis spiloides), an effective predator of rodents and other small animals. The large tracts of conservation lands protected by QUBS are vital to the Ratsnake’s  survival as the population in the Rideau Lakes is threatened; whereas in southern Ontario, it is endangered.

Grey Ratsnake

Of course, the underpinnings of any functioning ecosystem are its wealth of native plants and fungi, both macroscopic and microscopic. Fungi make up a very large percentage of the Earth’s biomass.  Then there are the invertebrates—the huge diversity of arthropods in Eastern Ontario, and the other invertebrate phyla—all forming the base of food and energy production for all of us vertebrates.  The previous blog post featured the entomology field course and just a sample of the insects to be found in the area around QUBS.  Here are a few more insects , other invertebrates and a small sample of the local plants.

Note that fungi will be the subject of my next post, Richard Aaron’s Fabulous Fall Fungi field course.

Widespread throughout North America and ecologically significant in our lakes, ponds and marshes, the Yellow Pond-lily (Nuphar lutea), pictured above left provides shelter, food and stabilization for many animals, including some of the aquatic invertebrates. To the right of the Pond-lily is a typical dragonfly (Order Odonata) nymph. The next photo is a freshwater crustacean (possibly the Waterlouse, a species of the genus Asellus, Order Isopoda). On the far right in this sequence of four photos, one of our Leech (Hirudinea) species is pictured.  Healthy ponds and lakes are teeming with these and many other invertebrates, zooplankton and phytoplankton, which provide the basic food for all larger species.

A Jagged Ambush Bug female (Phymata americana) munches on a fly, while two male Ambush Bugs attempt to mate with her.  All of this is happening amongst tiny Goldenrod (Solidago spp) flowers.  This is a LOT of biology in one photo!
A Jagged Ambush Bug female (Phymata americana) munches on a fly, while two male Ambush Bugs attempt to mate with her.  All of this is happening amongst tiny Goldenrod (Solidago spp.) flowers. This is a LOT of biology in one photo!

Laetiporus sulphureus

We will explore in great detail the world of the fungi in our next post. I didn’t see this fungus (above) during the fungi course though.  The Laetiporus sulphureus, which has a preference for Red Oak,  has several common names, including Sulphur Shelf and Chicken-of-the-Woods.

Above, these are aquatic Leaf Beetles, Donacia sp.,  mating and another common aquatic invertebrate, a Damselfly nymph (Odonata).

Monarch Butterfly caterpillar

We are not seeing as many of these on Milkweed as we have in the past.  In a walk with two other naturalists recently, we thought it would be approrpiate to change the name of the Common Milkweed to Monarch Flower, to honour this plant which hosts the Monarch Butterfly caterpillar, like the one shown above.

Hay field

Hay fields, as in the stunning photo above, are an excellent habitat to collect a wide diversity of insects and other Arthropods.  Lastly, the Grégory Bulté Ecology Field Course class of 2015.

Ecology Field Course class of 2015

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DNA insights into species distributions – trilling chorus frogs.

By Steve Lougheed

We have gained many ecological and evolutionary insights from studying variation in DNA markers, from resolving the very base of the tree of life (genealogical affinities of bacteria, archaebacteria/extremophiles, eukaryotes), through overturning received truths about mating systems of birds (most are not in fact genetically monogamous), to quantifying impacts of human activities on connectivity of populations of species of conservation concern. Among the many revelations that come from such DNA studies are those from phenotypically cryptic taxa whose appearances often mask deep phyletic diversity. Indeed an increasing number of studies shows that myriad, traditionally-regarded ‘species’ are in fact complexes of separate, reproductively-isolated species. DNA studies have revealed such cryptic species in many groups, including mammals (Ceballosa & Ehrlich. 2009), birds (e.g. Lohman et al. 2010), amphibians (e.g. Elmer et al. 2007), and insects (e.g. Hebert et al. 2004). Many examples of cryptic diversity come from the tropics, but here are also some intriguing examples from higher latitudes like ours, with implications not only for understanding of evolutionary affinities of taxa in question, but also for their geographical distributions and the forces that have shaped them.

The trilling chorus frogs (a distinct lineage or clade within the treefrog genus Pseudacris) comprise one such group. This clade, distributed broadly across eastern North America, includes at least nine species: the mountain chorus frog (P. brachyphona), Brimley’s chorus frog (P. brimleyi), spotted chorus frog (P. clarkia), Cajun chorus frog (P. fouquettei), New Jersey chorus frog (P. kalmi), upland chorus frog (P. feriarum), southern chorus frog (P. nigrita), boreal chorus frog (P. maculata) and western chorus frog (P. triserieta) (Moriarty & Cannatella 2004).

Two of these species occur in Ontario, P. maculata and P. triserieta. The two are very similar in appearance – both are small (generally < 3.5 cms in snout-vent length), with smooth skin, and a dorsum varying in colour from brown to greenish-gray, and a dark stripe through the eye and longitudinal markings on the dorsum. The calls too are very similar being comprised of a trill that is often likened to running one’s fingers along a plastic comb.  The boreal chorus frog was until recently considered to be distributed from northwestern Ontario to Alberta and north to the NWT, also being found in the USA in the Midwest south to Arizona and New Mexico. The western chorus frog was thought to range from southern Quebec and Ontario/northern New York state west to South Dakota, and south to the states of Kansas and Oklahoma (Harding 1997). In southern Ontario until recently there were considered to be two regional populations of P. triserieta: a “Carolinian population” found south and west of Toronto, and a Great Lakes–St. Lawrence population found east and north of Toronto, with the latter considered as ‘Threatened’ under the Canadian Species at Risk Act.

Boreal chorus frog from QUBS. N.A. Cairns.
Boreal chorus frog from QUBS. N.A. Cairns. Click on thumb for a larger image.

That’s the old view. Mitochondrial DNA evidence suggests that the Great Lakes–St. Lawrence population which was classified as P. triserieta is not in fact western chorus frog at all, but rather is a disjunct population of boreal chorus frog (Lemmon et al. 2007a,b, Rogic et al. 2015). Playbacks by Rogic et al. (2015) seem to affirm this, with eastern Ontario and western Quebec chorus frogs responding to previously recorded calls of P. maculata and not P. triserieta.

All of this has interesting implications for 1. Conservation (Is this western boreal chorus frog population genetically distinct and thus does it merit conservation priority?), 2. Biogeography (How did the species become disjunct and what paths of re-colonization did these distinct populations use?), and 3. Understanding the nature of species (these trilling chorus frogs are cryptic to us, but clearly they can tell each other apart – it is in the domain of mate recognition system and acoustics that the species differences are clear). As always there’s lots more work that can be done, not least of which is more finely mapping genetic diversity across the entire boreal chorus frog distribution.

References

  • Ceballosa, G. & P.R. Ehrlich. 2009. Discoveries of new mammal species and their implications for conservation and ecosystem services. Proc. Natl. Acad. Sci. USA 106: 3841–3846.
  • Elmer, K.R., J.A. Davila & S.C. Lougheed. 2007. Cryptic diversity, deep divergence, and Pleistocene expansion in an upper Amazonian frog, Eleutherodactylus ockendeni. BMC Evol. Biol. 2007, 7:247.
  • Harding, J. 1997. Amphibians and Reptiles of the Great Lakes Region. Univ. Michigan Press. Ann Arbor, MI.
  • Hebert, P.D.N., E.H. Penton, J.M. Burns, D.H. Janzen & W. Hallwachs. 2004. Ten species in one: DNA barcoding reveals cryptic species in the neotropical skipper butterfly Astraptes fulgerator.  Proc. Natl. Acad. Sci. USA 101: 14812–14817.
  • Lemmon, E.M., A.R. Lemmon, J.T. Collins, J.A. Lee-Yaw & D.C. Cannatella. 2007a. Phylogeny-based delimitation of species boundaries and contact zones in the trilling chorus frogs (Pseudacris). Mol. Phylogenet. Evol. 44:1068–1082.
  • Lemmon, E.M., A.R. Lemmon & D. C. Cannatella. 2007b. Geological and climatic forces driving speciation in the continental distributed trilling chorus frogs (Pseudacris). Evolution 61: 2086–2103.
  • Lohman, D.J., K.K. Ingram, D.M. Prawiradilaga, K.Winker, F.H. Sheldon, R.G. Moyle, P.K.L. Ng, P.S. Ong, L.K. Wang, T.M. Braile, D. Astuti & R. Meier. 2010. Cryptic genetic diversity in “widespread” Southeast Asian bird species suggests that Philippine avian endemism is gravely underestimated. Biol. Conserv. 143: 1885-1890.
  • Moriarty, E.C. and D.C. Cannatella. 2004. Phylogenetic relationships of the North American chorus frogs (Pseudacris: Hylidae). Mol. Phylogenet. Evol. 30: 409–420
  • Rogic, A., N. Tessier, S. Noël, A. Gendron, A. Branchaud & F0J. Lapointe. 2015. A “trilling” case of mistaken identity: Call playbacks and mitochondrial DNA identify chorus frogs in Southern Québec (Canada) as Pseudacris maculata and not P. triseriata. Herp. Rev. 46: 1-7.

Climate change impacts on frogs of Eastern Ontario.

by Stephen C. Lougheed

Leopard frog male.
Leopard frog male. Click on image to make larger. Photo by S.C. Lougheed.

Global climate change is anticipated to impact the natural world in myriad ways potentially causing shifting geographical ranges, and local or even global extinctions of species (Parmesan 2006, 2007). One possible manifestation of climate change is altered breeding or flowering phenology (e.g. Beebee 1995, Dunn and Winkler 1999, Chmielewski and Rötzer 2001, Kearney et al. 2010). My recently graduated M.Sc. student and QUBS alumna, Samantha Klaus, and I used historical “citizen science” data from the Natural Heritage Information Centre of Ontario and the Ontario Herpetofaunal Summary Atlas (http://nhic.mnr.gov.on.ca) to test whether there have been detectable shifts in the breeding phenology of Eastern Ontario frogs (Klaus & Lougheed 2013). We quantified both the timing of spring emergence and key aspects of the calling phenology of eight anuran species in southeastern Ontario, Canada, using an approximately 40-year data set. The leopard frog (Lithobates pipiens) was the only species out of eight considered that we found to emerge significantly earlier, by an estimated 22 days over the considered 4-decade span. Both L. pipiens and American toads (Anaxyrus americanus) seem to have advanced onset of calling significantly earlier by an estimated 37.2 and 19.2 days, respectively. Wood frogs (Lithobates sylvaticus) showed a trend towards earlier emergence by 19 days (although marginally insignificant in statistical analyses), whereas we detected no shifts in emergence phenology for the remaining five species. We also evaluated long-term climatic trends in Eastern Ontario based on data from three weather stations within our study area for 1970–2010. We found marked and significant increases in spring and summer average maximum temperatures. For example, mean maximum monthly March increased by approximately 0.07°C per annum for a total of 2.8°C over four decades. We also found evidence for changes to precipitation patterns. For example, there has been a significant decrease in average total precipitation in March (approximately 0.71 mm per annum, 2.84 cm total diminution over 40 years) and a significant increase for the summer month of June (0.89 mm per annum, for a 3.56 cm total over four decades). These observations are borne out anecdotally by the dismally wet June that we have had in 2013.

Amplecting American toads. Click on image to make larger. Photo by S.C. Lougheed.
Amplecting American toads. Click on image to make larger. Photo by S.C. Lougheed.

Our study illustrates that temperate zones such as ours are not isolated from the impacts of global climate change, and indeed shows that Eastern Ontario has already experienced marked shifts in local climate that are impacting local diversity in profound ways.

Literature cited.

  • Beebee, T.J.C. 1995. Amphibian breeding and climate. Nature 374: 219–220.
  • Chmielewski, F.M., & T. Rötzer. 2001. Response of tree phenology to climate change across Europe. Agric. For. Meteorol. 108: 101–112.
  • Dunn, P.O., & D.W. Winkler. 1999. Climate change has affected the breeding date of tree swallows throughout North America. Proc. Roy. Soc. B 266: 2487–2490.
  • Kearney, M.R., N.J. Briscoe, D. J. Karoly, W. P. Porter, M. Norgate, & P. Sunnucks. 2010. Early emergence in a butterfly causally linked to anthropogenic warming. Biol. Lett. 6: 674–677.
  • Klaus, S.P. & S.C. Lougheed. 2013. Changes in breeding phenology of eastern Ontario frogs over four decades. Ecol. Evol. 3.4 http://dx.doi.org/10.1002/ece3.501
  • Parmesan, C. 2006. Ecological and evolutionary responses to recent climate change. Annu. Rev. Ecol. Evol. Syst. 37: 637–669.
  • Parmesan, C. 2007. Influences of species, latitudes and methodologies on estimates of phenological response to global warming. Glob. Change Biol. 13: 1860–1872.

Grey treefrog rejected as food by a fisher

Fisher (Martes pennanti). Photo: Mark Andrew Conboy.

Fishers (Martes pennanti) have become a relatively common species in Eastern Ontario over the past three decades but for such a potentially important predatory mammal we know very little about them at QUBS. Very few observations of the foraging behaviour and diet of fishers have been made at the station. Fishers have been seen eating and caching carrion in winter and pursing small mammals along rocky outcrops in spring.

Observing fisher foraging in real time is difficult, but following fisher tracks is an alternative method of gathering behavioural information. On February 28, 2010 I followed fisher tracks for 1.7 km on the Pangman Tract. Over that distance I noted one occasion where the fisher stopped to investigate a large bone, one scat deposit and four places where the fisher dug into the snow and/or the exposed leaf litter. Two of those digs were in the duff at the base of eastern white pines (Pinus strobus). Another dig was in the leaf litter beside a log. In all three cases it was impossible to determine what the fisher was digging for, but I suspected it may have been trying to find hibernating frogs. On the fourth dig I found a hole 13 cm deep through snow and humus beside which was a tetraploid grey treefrog (Hyla versicolor); the frog appeared to be dead, though it was not at all damaged by the fisher. Treefrogs normally freeze solid during hibernation but this frog was completely thawed. I took it back to the station to see if it would revive, but it never did.

Tetralpoid grey treefrog (Hyla versicolor) that was dug out of a hole (right) by a fisher. Photo: Mark Andrew Conboy.

At first I was puzzled by the fisher’s rejection of the treefrog, but Fred Schueler reminded me that grey treefrogs are unpalatable to shrews and probably other mammals. The bright orange-yellow markings on the treefrog’s legs probably serve as an aposmatic warning to would-be predators. Not all of our frogs are so distasteful. Wood frogs (Rana sylvatica), for example, also hibernate in the leaf litter and may have been the intended prey of the fisher. – Posted by Mark Conboy