Connecting people with nature in Ontario's Mississippi Valley
Mississippi River at Pakenham

Dr. Henri Goulet

‘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.

Carabus vietinghoffi (1024x768)

 

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!

 

Elaphrus clairvillei (1024x901)

 

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.

Ground Beetle talk (1024x768)

 

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.

 

 

 

 

Press Release
Mississippi Valley Field Naturalists
Submitted by: Mike McPhail
Thursday Feb. 3, 2005

Naturalists learn of smallest backyard creatures

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It has been said that biodiversity is the key to ensuring the continuance of life on earth. During the Jan 20th lecture on Insect Biodiversity in the Mississippi Valley Field Naturalists (MVFN) Biodiversity series, research scientist Dr. Henri Goulet’s knowledgeable and passionate presentation highlighted an important issue, just how little we actually know about the living organisms in our own backyards. Insects and other arthropods are by far the most diverse of small life forms in Ontario, yet Dr Goulet estimates that we know less than 50% of the species.

Attendee’s, who braved the frigid temperatures of the night, were presented with absolutely dazzling slides of some of the 230 species of insects alone that frequent a few flowering heads of goldenrod. It truly is a jungle out there with insect species representation from herbivores, parasites, predators, and nectar & pollen feeders. To put this diversity in perspective, during this year’s Carleton Place Christmas bird count, 45 species of birds were recorded in a 15-mile diameter circle around the town of Carleton Place.

Biodiversity is considered a fundamental requirement for adaptation, survival and continued evolution of species and Dr Goulet’s microscopic insect world was alive with insects adapt at cryptic hiding, mimicking patterns that would make them less susceptible to or better at predation. As each of us gains a better understanding of biodiversity, we will be able to make better decisions about our environment, starting in our own backyards. Such as taking Dr Goulet’s lead, who, after noting their genocidal effects, declared his own backyard drug (pesticide) free. Dr Goulet was kind enough to share with the MVFN some of the presentation’s slides (such as a preying mantis mimicking a wasp), which will soon be posted on www.mvfn.ca

Mark your calendars for MVFN’s 5th Biodiversity lecture (Communicating the Issues of Biodiversity), that will be given by Andrea Howard of the Eastern Ontario Museum of Biodiversity on Thur. Feb. 17th at the Almonte United Church, 106 Elgin St. at 7:30 pm. If you are not yet a member of the MVFN, this may be a good time to join. For further information, please contact MVFN Programme Chair Tine Kuiper, 256-8241 or consult our web site: www.mvfn.ca

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FULL-SIZED  CALENDAR WITH DETAILS

MVFN natural history talks:  7:30 pm on third Thursdays of Jan, Feb, March, April,  Sept, Oct, and Nov at Almonte United Church, 106 Elgin St. Almonte ON. All welcome! Non-members $5. 

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