Canadian Entomology – Page 6 – Entomological Society of Canada

Recreational boating affects dragonflies

—-By Aaron Hall—-

A typical adult dragonfly. Note the spiked legs, which are held in a basket shape to help catch prey while flying.

A typical adult damselfly. Note the spiked legs, which are held in a basket shape to help catch prey while flying.

Dragonflies are charismatic insects, and most of us can probably remember chasing them or watching their acrobatic flights when we were children. But what most of us didn’t realize when we were kids, is that dragonflies spend the majority of their lives as toothy, alien-looking predators living underwater before they become adults. Depending on the species, they can live in the water for several weeks up to several years.

A typical larval dragonfly, which feeds on other aquatic animals – and even other dragonflies!

By living part of their lives in water, and part on land/in the air, dragonflies represent an interesting conservation challenge. Historically, conservation science has focused on single habitats, such as lakes, streams, forests or grasslands. Little attention has focused on incorporating multiple habitat types, such as those required by dragonflies, into conservation, potentially leaving species like dragonflies in danger.

In the Waubaushene area of Georgian Bay (Lake Huron), recreational boating is very common. These boats create waves that can dislodge both adult and larval dragonflies, affecting their ability to find food and avoid predators. The overall number of boats, the speed of these boats, and how close they are to coastal wetlands are the most important factors that determine how impactful boat-generated waves are on dragonflies. My colleagues and I at the University of Toronto investigated how much influence these recreational boats have, relative to more natural processes, on dragonfly communities in Georgian Bay.

A Google Earth image of an area in Georgian Bay. Note the many waves created by boats as they travel through this region.

Taking the lead on this project, I counted dragonflies from 17 islands in Waubaushene. The coastal wetlands around these islands are inhabited by dragonflies. The islands studied in this project were selected to represent a range of influence from boats in the area, determined by their distance and orientation to marked boating channels and area marinas.

Aaron Hall counting adult dragonflies at one of the islands in Waubaushene.

The results show that boats do have an influence on dragonfly communities, providing a link between recreational boating and dragonfly communities. This research provides important insights that can be applied to the protection and conservation of dragonflies, and suggests that some very simple changes in boater behaviour could have big implications. For example, if boats travel slower or further away from dragonfly habitats, they would have less impact. These two factors might be simple to change. In areas where boats mostly stay within marked boating channels, if these channels were moved or adjusted so they are as far away from dragonfly habitats as possible, impacts would be minimized. Additionally, speed limits could be set in these channels to reduce the size of waves created by boats. These simple measures could have a positive impact on dragonflies, which are a critical component in the aquatic and terrestrial foodwebs of this region.

Want to know more? This research is published in the journal Insect Conservation and Diversity. You can also follow me on Twitter @aarohall.

May 14, 2015/by escstudents

Academic, Canadian Entomology, ESC Blog, Fieldwork

Behavioural observations in nature reveal mating strategies of jumping spiders

—- By Gwylim S. Blackburn & Wayne P. Maddison—-

Animals reveal a lot about their lives simply by the way that they behave. When observed in the wild, they also offer insights to the function of behaviours in a natural context. Capturing these insights just requires a little patience, and attention to the right details.

In a recent study printed in the journal Behaviour, we set out to document Habronattus americanus jumping spider behaviors that would shed light on their ‘mating strategies’—the tactics used by females and males to acquire mates. Specifically, we wanted to know if males show off their flashy displays only to females or also compete directly with each other, if they invest heavily in mate search, and if females are choosy when deciding who to mate with.

An adult male Habronattus americanus jumping spider travels through beach habitat in British Columbia, Canada. The bright coloration on his face and legs is presented to females during elaborate courtship dances. Photo credit: Sean McCann.

To pursue these issues, we followed 41 adults for up to 30 minutes each, and we also staged interactions between an additional 36 male-female pairs, in natural habitat.

Typical Habronattus americanus habitat is fairly flat, well-drained, and sparsely covered with plants, sticks, or pebbles. Photo credit: Maxence Salomon

The behaviours of both sexes pointed quite strongly to indirect male competition for choosy females. Males did not display to (or fight with) each other. Instead, they travelled far and wide, eating nothing but displaying to every female they met. Females, on the other hand, focused on hunting rather than travel, and they almost never permitted copulation despite the vigorous courtship efforts of males.

Collectively, these behaviours supply deeper lessons than their individual functions; they also indicate how natural selection might shape several of the traits involved. In particular, our findings suggest that female mate choice may be the key source of selection favouring the evolution of male display traits.

An adult female Habronattus americanus jumping spider in natural beach habitat. Females are avid hunters. Photo credit: Sean McCann

The apparently high investment by males in mate search also represents a potential factor shaping female mate preferences. In a variety of other species, mate search costs have been shown to provide a way for females to judge the quality of prospective mates. This is because males who are able to pay those costs while still producing an impressive display can make better fathers (e.g., by providing better parental care, or by passing along advantageous genes to their offspring). To determine if this is the case in H. americanus, further research will be needed to see how male condition is linked to the quality of their displays and the success of their offspring.

The Habronattus jumping spiders are famous for their stunning array of male displays. It would be fascinating to know how mating strategies, and the natural surroundings in which they unfold, have influenced this diversity. Behavioural observations of different species in the wild will be essential for getting at this question.

May 11, 2015/2 Comments/by escstudents

Canadian Entomology, ESC Blog

Decoding the love songs of mate-seeking male bark beetles

—–By Amanda Lindeman, PhD Candidate, Carleton University—–

A male red turpentine beetle over the sound wave of a train of its interrupted chirps.

In April 2015, I coauthored a paper on what bark beetles are trying to say to each other when they interact with potential mates (1). No one knew for sure – since bark beetles, as their name implies, live under the bark, males could simply be announcing their presence as they wander the surface of the bark trying to join a mate in her gallery below, they could be advertising their species identity to make appropriate mate pairings or to say “Hey! I’m not a predator, let me in!” But the thing that always struck me is that many of the 5000+ species of bark beetles produce sounds, and their sounds are complex — they produce more than one kind of sound, and they can be multi-component. For a group of animals that already produces intricate attraction pheromones, why produce sound at all? Is it just for the sake of redundancy?

An elm bark beetle gallery located along the inner bark of an elm tree. The female digs the central (vertical) gallery and waits at the entrance of the gallery for a male to join her. Eventually, she will lay her eggs along the sides of the gallery and as the larvae hatch they will tunnel out causing the radiating (horizontal) galleries.

Before I go too far, perhaps I should go waayyyy back, and explain why I find insect sounds to be so interesting in the first place. I think that animal communication has always captured human attention and imagination as we consider both the beauty in animal sounds and what they mean. The dawn choir of birds; the roar of a lion; the squeak of a mouse. But, as Frank E. Lutz (1924) said: “probably the first definite sounds made by land-animals on this earth were made by insects. Before ever birds sang or even frogs croaked”. Insects led the way. Indeed, many insects have beautiful songs appreciated by people since antiquity when crickets were kept as domestic pets in ancient China (3) and cicadas were kept in cages in Greece and Rome (4), not unlike how we would keep a pet bird today. Apart from those musically talented insects, however, we need to remember that even in “the lowest insect tribes, many a rough, rasping note, though awakening no particular delight in us, serves as great a purpose as the more pleasant sounds” – F. C. Clark (1875). The trouble in research often comes down to finding out what that purpose is.

No group embodies this sentiment more than the beetles, an order with more ways of producing sound than any other, and yet with a very poor and widely neglected understanding of the purpose of those sounds (5). Bark beetles are an incredibly interesting group of beetles, who likely first caught our interest because of their destructiveness. The members of the genus Dendroctonus in particular have been hailed by forest entomologists as being “the most destructive enemies of the coniferous forests of North America” (6) and “the greatest tree killers known”(7).

One species in the genus that is no stranger to Canadians is the mountain pine beetle, and to put things in perspective, this beetle has impacted over 18 million hectares of forest in BC, and killed about 50% of the total volume of commercial lodgepole pine in only two decades. And, as I mentioned above, I personally find them particularly interesting because of their complex sounds which many of them invariably make as they approach the gallery of a potential mate and try to enter.

A male red turpentine beetle at the entrance to a female’s gallery. Female is visible blocking the gallery entrance.

A male red turpentine beetle at the entrance to a female’s gallery. The female is visible blocking the gallery entrance.

So, getting back on point, what do these sounds mean? In one species of the destructive Dendroctonus genus, the red turpentine beetle, I found that many aspects of a male’s courtship song correlated to his size. Since male size is linked to his ability to produce more offspring, this means that the male might be using his chirping as a way to honestly tell the female how fit he is. One important chirp variable related to size was the number of components per chirp. Chirps with just one component are termed “simple” while chirps with more than one component are termed “interrupted” and sound like a stutter in the chirp to the human ear. It turns out larger males have more components in their chirps. Also, and importantly, females always admitted a male into her gallery if he made interrupted chirps, while if he only made simple chirps, or was experimentally muted to produce no sound at all, he would only be successfully accepted approximately 60% of the time.

Even though I find the question of why an animal produces sound to be inherently interesting, someone who has unfortunately been a bark beetle victim and has seen local communities and businesses devastated by these insects might not care so much about the why and instead wonder what next? Now that we know that sounds may be important to the life history of bark beetles and that their chances of successful mating might depend to some extent on these signals, can this help us manage them? Probably! Acoustic technologies have helped control pest insects by using the sounds the pests rely on against them (8). This can mean anything ranging from detecting their presence to manipulating their behaviour. These kinds of technologies have not yet been applied in bark beetle management because we haven’t known enough about their sounds to develop strategies. Hopefully, as we begin to understand more about the purpose of their sounds, we can use acoustic technology to develop new targeted solutions to this serious problem.

Amanda Lindeman with a funnel trap (baited with pheromones and host tree kairomones to attract bark beetles) – photo credit: Michael Connolly.

References

(1) Lindeman, A.L. & Yack, J.E. (2015) What is the password? Female bark beetles (Scolytinae) grant males access to their galleries based on courtship song. Behav. Proc. 115:123-131

(2) Lutz, F.E. (1924) Insect sounds. Am. Mus. Nat. Hist. 50:333-372.

(3) Laufer, B. (1927) Insect Musicians and Cricket Champions of China. Field Museum of Natural History Leaflet

(4) Clark, F.C. (1875) The song of the cicada. Nat. 90(2):70-74.

(5) Wessel, A. (2005) Stridulation in the Coleoptera – An overview. Insect Sounds and Communication. 397-430

(6) Hopkins, A.D. (1909) Practical information on the Scolytid beetles of North American forests. I. Bark beetles of the genus USDA Bur. Entomol. Bull. 83. 169 pp.

(7) Wood, S.L. (1963) A revision of the bark beetle genus Dendroctonus Erichson (Coleoptera: Scolytidae). Great Basin Nat. 23:1-116.

(8) Mankin, R.W. et al. (2011) Perspective and promise: a century of insect acoustic detection and monitoring. Ent. 57(1):30-44.

May 6, 2015/1 Comment/by escstudents

Canadian Entomology, ESC Blog, Natural History, Uncategorized

Finding a rare robber fly in the Okanagan

Vaseux Lake, a gorgeous body of water in a dry landscape.

Catherine Scott and I recently indulged in an almost unheard-of pleasure…A week long car camping trip to the Okanagan Valley! For those of you who don’t know, this is the area where the vast majority of BC wines originate (and tree fruit crops as well!). The South Okanagan and the Lower Similkameen Valleys, biologically speaking, are very similar to a desert, with many of the flora shared with northern parts of the Great Basin Desert.

The purpose of the trip was to have fun and seek out whatever cool life-forms we could, basically doing undirected fieldwork. With Catherine along, it meant that we sought out a LOT of spiders, but the Okanagan has some spectacular ones, so I was not complaining.

Catherine under the rocky slopes off McIntyre Rd.

While soliciting info about good spots to check out, one of our Twitter contacts told us to be on the lookout for Efferia okanagana, a robber fly (Asilidae), recently described by Rob Cannings in The Canadian Entomologist.

The bluffs are spectacular, with abundant scree slopes, which can produce something terrifyingly called a “debris torrent” at times.

On the 5th day of our trip, we were examining the awesome bluffs above the eastern shore of Vaseux Lake (thanks Nature Trust!), when we spotted our first robber. I managed to get a dorsal shot of this female, followed by a couple lateral shots.

We took these to a local restaurant with Wi-Fi, and compared them to the pictures of E. okanagana in the paper. They looked mighty similar! We went on Twitter to ask Dr. Cannings if these were indeed the Efferia we were looking for. They were!

This robber is at significant risk of extinction due to its small range in Canada (to date it has not been collected in Washington State). The South Okanagan grassland habitats where this and other iconic wildlife make their living are at risk due to widespread development and increased agricultural land use. It is one of the earliest-flying robbers in the area, and photographs have documented it feeding on a wide variety of insect taxa. Like other large Efferia, they are not super difficult to approach, flying in bursts when disturbed and often coming to rest only metres away.

The very next day, coincidentally World Robber Fly Day (thanks to Erica McAlister of the Natural History Museum), we set out for the bluffs once more (they are an awesome habitat). We managed to find E. okanagana several more times, including a female feeding and a pair in copula!

A female Efferia okanagana chows down on what looks like an ichneumonid.

Eating requires a leg bath afterward.

A pair of Efferia okanagana copulating! The male seems to partially cover the female’s eyes with his tarsi.

Look at the odd position of the male’s abdomen!

A male, note the bulbous rear end.

Catherine after an awesome trip to the bluffs above Vaseux Lake.

May 6, 2015/4 Comments/by Sean McCann

Canadian Entomology, ESC Blog, Students

Royal honours for Canadian student!

Eloise Rowland, graduate of the Gries Lab of Simon Fraser University was recently recognized by the Royal Entomological Society for the best paper published in the journal Physiological Entomology in 2013 and 2014. This paper, part of Eloise’s MSc work, examines the role of sound in the sexual communication of the gypsy moth, Lymantria dispar. It was coauthored by Peter Belton, Paul Schaefer and Gerhard Gries and is really a great contribution! Check it out!

Rowland E, Belton P, Schafer PW, Gries G. 2014. Intraspecific acoustic communication and mechanical sensitivity of the tympanal ear of the gypsy moth Lymantria dispar. Physiological Entomology 39(4): 331 – 340. DOI: 10.1111/phen.12080

March 24, 2015/by Sean McCann

Academic, Acadian Entomological Society, Canadian Entomology, ESC Blog, Outreach/Education

“Thrips” should die

By Dr. Tom Chapman, Memorial University

—-

I used scissor to cut my pant into short. A jarring opening sentence, I know. It is how I use to feel when someone dropped the “s” in “thrips”; it is a plural noun, don’t you know? If you see a solitary individual of these animals it is still referred to as a “thrips”. I have been quick to correct people that have made this mistake. But lately on this issue, I have become tired of being the grammar pedant.

Art work done by Michael McLeish and Andrew Chaulk.

I don’t mean to be insulting to the readers of this blog, I am assuming you are knowledgeable and enthusiastic about insects, but just maybe you haven’t heard much of thrips. They are members of the insect Order Thysanoptera, and world wide there are at least 5000 species. They are small; in fact, they are typically the size and colour of the commas in this very sentence. These slithering punctuation marks do not commonly attract the attention of insect enthusiasts. However, for a small number of economically important species there is a large and vibrant community of researchers. These scientists routinely gather together to describe and discuss their research outcomes, with their next big event to be held in California (2015, Xth International Symposium on Thysanoptera & Tospoviruses). Among the dominant applied work that will be presented at this meeting, and those of the past nine meetings, will also be more curiosity driven research. This group of non-applied thrips-focused researchers could book a table at most restaurants. No more or less important, just a more private club. A club I joined as a PhD student.

Professor Bernard Crespi, in his early career, did a stint in Australia as a Research Associate. His motivation to travel to the antipodes was to answer the challenge, are there social thrips? The evolution of altruism (sub-fertility in part of a population) in the insects was and remains an outstanding conundrum for evolutionary theory. Theoretical attempts made in the sixties and seventies to explain these incidences of self-sacrificing castes appeared to also predict that somewhere within the diversity of thrips species we should also find sociality. There were no ready examples. Crespi had a hunch that social thrips would be found among the gall-inducing thrips on Australian Acacia. In brief, he was right! Subsequently (Again, drastically shortening the story. Hey, I am not trying to write Crespi’s biography here.), Crespi took a position at Simon Fraser University where his research began with a focus on Australian social thrips. I was the first graduate student he recruited.

I will admit that the thrips played no part in attracting me to the program. Instead, it was Crespi’s strong scientific reputation and the chance to do field work in Australia that was the lure. However, it was several years of working in Canada with preserved and frozen specimens of thrips before I saw their full charm in their native habitat. I was hosted in Australia by Crespi’s major collaborator with the thrips work, Dr. Michael Schwarz, at Flinders University. In this prominent social insect lab I met three students with the same taxonomic focus as me. Like Tigger in The Tigger Movie, I had started to fear that I was the only one. We connected quickly, and one of the pivotal bonding events happened during a trip to a Nursery outside the city of Adelaide. We needed native Australian plants for an experiment and the Nursery that could provide them was located inside a national park. On the way in we saw a sign warning visitors that they were not permitted to bring in plants or soil for fear of introducing pests. The list of pests included “thrip”. On our way out of the park, we stopped our truck; one of us jumped out with a permanent marker and added an “s”. Having scored one for thrips, we cheered and drove away.

It has been almost twenty years since we vandalized that sign (I hope that is longer then the crime’s statute of limitation). Since then I have continued research on social thrips, and I have given lectures in undergraduate and graduate classes, job interviews, conferences, public lectures and even dinner parties. Many people have engaged me after these events to express further interest in the work. If they said “thrip”, I corrected them. I thought educating people outweighed the potential risk of embarrassing them. My behaviour has certainly lost me a few acquaintances, some people have skin that is thin, but is there any evidence that I have been successful in educating people? I think the answer is no. A student of mine was interviewed a little while ago on the national radio science show, Quirks and Quarks. She corrected the host when he dropped the “s”. Two students and I submitted a paper to an entomological journal, and one reviewer pointed out to the editor the poor grammar of our presentation. The example they used to illustrate our incompetence was our failure to drop the “s”. I am co-writing a book chapter with a longtime friend and colleague, he edited my part by dropping a few of the “s”s. I give up. Not research or a fascination with thrips, just the “s” thing. It is now my opinion that the thrips research community is better off without this plural noun. To the uninitiated it sounds weird to use “thrips” in the singular, and to insist on its proper use is alienating. I don’t know how to change this. Who is in charge? How do you start a revolution? In the mean time, to those that naturally say “thrip” I am sorry I have offended you, let’s be friends.

March 16, 2015/by Blog

Canadian Entomology, ESC Blog, Students

ESC Students Entered in NSERC-CRSNG Video Contest

Two student members of the Entomological Society of Canada have videos entered in the NSERC-CRSNG Science, Action! competition. The contest, open to students across Canada, aims to share NSERC-CRSNG funded research through 60 second videos, and offers a cash prize of $3,000 to the winning entries. The first round of public voting is now open, and both students would appreciate your support by viewing and sharing their entries, helping highlight entomology research in Canada.

Michael Hrabar, MSc Student at Simon Fraser University

Bed bugs have become a global epidemic. Detecting infestations early is the key to successful eradication. Scientists at Simon Fraser University have identified the bed bug aggregation pheromone. They extracted the pheromone from the bugs’ feces and cast cuticle, and analyzed extracts by state-of-the-art technology including gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy. In lab and field bioassays, they demonstrated that a 6-component pheromone blend is highly effective in attracting bed bugs to, and retaining them in, cardboard shelter traps. The pheromone technology can now be developed as a tool to help detect, and possibly control, bed bug infestations.

Morgan Jackson*, PhD Candidate at the University of Guelph

Flies, two-winged insects in the order Diptera, are an important and understudied component of Canada’s biodiversity. With nearly 8,000 species known from Canada, and likely as many more still to be discovered, flies impact our lives every day, either as pests and disease vectors, or as pollinators, decomposers and in many other ways. At the University of Guelph Insect Collection, we’re working to understand the diversity of flies from coast to coast and beyond our borders by studying their natural history and taxonomy using comparative morphology and DNA. By combining fieldwork with museum-based research, we’re helping catalog Canada’s dipteran diversity.

*Disclaimer: Morgan Jackson is an administrator of the ESC Blog.

March 13, 2015/by Morgan Jackson

Academic, Canadian Entomology, ESC Blog, Research

Canadian Entomology Research Roundup: January 2015 – March 2015

As a graduate student, publishing a paper is a big deal. After spending countless hours doing the research, slogging through the writing process, soliciting comments from co-authors, formatting the paper to meet journal guidelines, and dealing with reviewer comments, it’s nice to finally get that acceptance letter and know that your work is getting out there.

We are continuing to help publicize graduate student publications to the wider entomological community through our Research Roundup. The ESC Student Affairs Committee is happy to be posting a second roundup of papers authored by Canadian graduate students. If you published an article recently and would like it featured, e-mail us at entsoccan.students@gmail.com.

For regular updates on new Canadian entomological research, you can join the ESC Students Facebook page or follow us on Twitter @esc_students.

So, what’s hot off the press, you ask? Here’s what some entomology grad students have been up to between 31 January 2015 and 4 March 2015:

Systematics and Morphology

Piophilidae is an important family of flies to forensic entomology: their occurrence on a corpse can help determine post-mortem interval and assist legal investigations. Sabrina Rochefort (McGill University) and colleagues provide an updated key to the forensically pertinent Piophilidae in the Nearctic Region. Article link

Job Opening – Entomology Curator, Royal British Columbia Museum

After an outpouring of support from the Canadian entomological community, the Royal British Columbia Museum has decided to hire a new Curator of Entomology!

The competition for the Curator of Entomology position at the Royal BC Museum is now posted at http://royalbcmuseum.bc.ca/assets/Posting3.pdf. Deadline for applications has been extended to 24 March.

March 3, 2015/by Blog

Canadian Entomology, ESC Blog, Meetings, Societé d'Entomologie du Québec

Announcement – ESC-SEQ JAM 2015!

The Entomological Society of Canada and the Société d’entomologie du Québec are pleased to invite the entomological community to the 2015 Joint Annual Meeting in Montréal, Québec. The conference will take place from 8^th to 11^th November, and includes a range of symposia and associated events under the meeting’s theme : Entomology in the Anthropocene.

The plenary symposium is designed to provide a provocative overview of the challenges related to entomology in the Anthropocene. Plenary speakers include Dr. May Berenbaum (University of Illinois at Urbana-Champaign), Dr. Jessica Hellmann (University of Notre Dame), and Dr. Marcel Dicke (Wageningen University).

The Entomological Society of Canada and the Société d’Entomologie du Québec invite proposals for symposium sessions at the 2015 Joint Annual Meeting (JAM). We invite timely and well organised submissions from across the breadth of entomological science. We are particularly enthusiastic about symposia that are aligned with our 2015 meeting theme “Insects in the Anthropocene.” Deadline for symposium submission is the 28^th February. See the webpage Call for symposia.

Sunday Nov. 8th, 7-10pm; Eat, drink and mingle with new and old friends at the ESC-ESS JAM Opening Reception at the Montréal Insectarium. Entomophagous appetizers will be served.

For more information, please visit our website, join us on Facebook and on Twitter using the hashtag #ESCJAM2015.

February 19, 2015/by Blog