Posts

, ,

Citizen Science on a continental scale

The Editor’s pick from the Feburary issue of The Canadian Entomologist is Crowdsourcing for large-scale mosquito (Diptera: Culicidae) sampling by Elin C. Maki and Lee W. Cohnstaedt. In this blog Lee Cohnstaedt reveals more about the research.

—-

“We were inspired to carry out this study to find out the origin and historical geographic spread of the disease vector mosquito species Culex tarsalis and Aedes vexans. By collecting throughout the entire mosquito habitat range, we generated a snap-shot in time of the distribution of mosquito genes. However, collecting mosquitoes throughout the continental United States was not feasible for one lab. Therefore we used social networking and crowdsourcing to solicit specimens from public health officials, mosquito control experts, and citizen scientists. The response was incredible.

Image courtesy of Sarah Edwards.

Image courtesy of Sarah Edwards.

We hope a lasting impact of this project beyond advancing public health safety for humans and food security for agriculture, is demonstrating the importance and unique capabilities of the public health and mosquito control infrastructure in the United States. These agencies continually face budget cuts because their importance is undervalued. In addition to their public health roles, they contribute substantially to research which is an underappreciated role at improving public safety. This large-scale project would not be possible without the agencies volunteering their time, energy, and expertise. These agencies and individuals contributed to an unprecedented mosquito collection on a continental scale and we feel the North American Mosquito Project will continue to ask big questions with the help of network contributors in the future.

This research will lead to the mosquitos being used for three projects: First, the mosquito samples will be processed for population genetic and phylogenetic analysis to determine mosquito migration currently and historical spread. Second, the movement data from the genetics will be used to parameterize mathematical models to predict the spread of mosquito-borne exotic or emerging pathogens. This will improve public health safety and food security an important role of the agencies that contributed mosquitoes. Third, specific genes unique to certain populations (private alleles) will be examined to understand their role in range expansion.

Entomologists are very friendly people and we were amazed at how kind and helpful people were throughout the project. At least 25% of the network consisted of people we never contacted; other contributors contacted them and asked them to help. Similarly, some individuals collected from huge areas or contacted people to cover entire regions of the country. It makes us proud to be a part of the community and hopefully we can return the generosity with useful information.”

Read the full article here until 22nd May 2015.

, , , ,

Exploring piophilid flies: taxonomic tools for forensic entomology

By Sabrina Rochefort, MSc student, McGill University.

Early in my undergraduate program at McGill University, I was looking for an opportunity to volunteer in a lab, where I could feed my need to learn and make new discoveries. That led me to Terry Wheeler’s lab; he was the teacher for my evolution class at that time.

I had a strong interest in evolution and paleontology, and was hoping to pursue that field. But Terry informed me that volunteering in his lab did not involve studying fossils, but instead studying tiny insects. Curious and willing to learn about insects, I decided to give it a try! At the Lyman Museum, I quickly discovered that entomology is a field of study with great opportunities and with an infinite number of projects. Besides studying for my degree, and working on weekends at Tim Hortons, I was volunteering up to 12 hours a week, between and after classes, pinning flies and identifying them. I couldn’t lie to myself anymore, I had developed a strong passion for entomology!

??????????

Identifying flies at the Lyman Museum. Photo by E. Vajda

 

Volunteering gradually transformed into a student job. It’s then that Terry introduced me to the fly family Piophilidae, commonly known as the Skipper Flies. I spent numerous hours familiarising myself with piophilids, reading literature, learning to identify them, their ecology, etc. All that knowledge that I acquired in entomology during my undergraduate studies gave me a great opportunity: the chance to pursue graduate studies. I am presently undertaking a Master’s project on the taxonomy and phylogeny of Piophilidae.

Image 2

Collecting piophilids on decaying mushrooms in the Yukon. Photo by E. Vajda

 

Now, let’s put a little less attention on my background and a little more on this wonderful family of flies and my project!

Piophilids are small to medium flies (3 to 9mm), which are abundant and diverse, especially in the northern hemisphere. To date, there are 82 described species worldwide. They mainly feed and reproduce on decaying organic matter. This family is of interest in several scientific domains such as forensic entomology (for their presence on carrion), in behavior (for their unique sexual selection strategies) and in biodiversity (for their interesting geographic distribution in the arctic). Several species are also pests in the food industry. The study of their taxonomy and phylogeny is essential for several reasons: to be able to identify specimens found in studies; to document the geographic distribution of species; to establish their phylogenetic relationships; and to learn more about their biology and ecology. The main objectives of my thesis are a taxonomic revision of the Nearctic Piophilidae and phylogenetic analysis of the genera worldwide.

Liopiophila varipes, a piophilid species commonly found on carrion. Photo by S. Rochefort

Liopiophila varipes, a piophilid species commonly found on carrion. Photo by S. Rochefort

A statement that is often repeated in our lab is that it is important for taxonomists and ecologists to collaborate, and that the outcomes of our taxonomic projects should be useful not only for taxonomists but also to other entomologists in other fields of expertise. And that is right! For taxonomy to make sense, it is essential that other researchers be able to understand it and use our work. This can be done by providing them with “working tools” such as identification keys which are simple and adapted to a specific need. It is for that reason that, as a side project to my thesis, I decided to collaborate with Marjolaine Giroux, from the Montreal Insectarium, Jade Savage from Bishop’s University and my supervisor Terry Wheeler on a publication and key to the Piophilidae species that may be found in forensic entomology studies in North America. That paper has just been published in the Canadian Journal of Arthropod identification. We reviewed some of the problems associated with identification of piophilids, and the need to develop a user-friendly key to the species. We wanted to create a key with lots of photographs, that was user-friendly and simple for non-specialists, and that would be published on-line and open access. Because of this, CJAI was the ideal journal for our paper.

Seeing this publication completed early in my graduate studies is a great accomplishment for me. It gave me the opportunity to share my knowledge and make taxonomy more accessible to students, amateur entomologists and researchers in the academic and scientific community. Undertaking a project in a less familiar field which is linked to your expertise is a very gratifying experience which I strongly encourage other students to try. From this experience, I acquired new skills and knowledge, I made connections with researchers in other fields of study and I was able to make more connections between my Master’s thesis and other subjects in entomology.

Reference

Rochefort, S., Giroux, M., Savage, J., Wheeler, T.A. 2015. Key to Forensically Important Piophilidae (Diptera) in the Nearctic Region. Canadian Journal of Arthropod Identification No. 27: January 22, 2015. Available online

, , , , ,

African fig fly shows up in Canada: first occurrences of another fruit-infesting fly and potential pest.

By Justin Renkema, Post-Doc, University of Guelph

—–

It was an early morning after a long drive from Guelph to a small fruit farm in Chatham-Kent where my undergraduate student, Caitlyn, and I were conducting a small-plot spray trial to test the effect s of repellents against Drosophila suzukii (Spotted Wing Drosophila), a recent invasive and serious fruit pest.  I knew the raspberry patch was heavily infested with D. suzukii so before getting to work, to amuse ourselves at the start of the day, I started gently shaking canes, and we watched the swarms of fruit flies disperse and hover over the fresh fruit.  However, as I went to grab a branch low to the ground, I noticed something different about one of the fruit flies sitting on a leaf.  It had characteristic white “racing stripes” along its thorax, unlike any other fruit fly I had seen.  This was it!  This was very likely Zaprionus indianus or African fig fly, another invasive and potential fruit pest that we knew was moving northwards from the southeastern USA.  Caitlyn grabbed a vial and we successfully had, on 10 September 2013, what we thought was the first capture of this fly in Ontario and Canada.

Zaprionis indianus photographed by Dr. Stephen Marshall in Africa. (Photo C Stephen A. Marshall, used with permission)

Zaprionis indianus photographed by Dr. Stephen Marshall in Africa. (Photo © Stephen A. Marshall, used with permission)

 Indeed the fly was Z. indianus, as determined by Meredith Miller, a M.Sc. student at the University of Guelph working on taxonomy of Drosophila spp. in Ontario.  Through contact with Hannah Fraser at Ontario Ministry of Agriculture Food and Rural Affairs, we learned that their Ontario-wide monitoring program for D. suzukii had also picked up some African fig flies in apple-cider vinegar traps, and a few at an earlier date than our find in Chatham-Kent.  Colleagues in Quebec (Jean-Phillipe Légaré and others at MAPAQ) had also found what they believed were Z. indianus.  Once all the material was collected and examined by Meredith, we submitted a scientific note documenting our Z. indianus discovery in Canada that was published by the Journal of the Entomological Society of Ontario.

Zaprionus indianus is native to the Afrotropical region.  It was found in Brazil in 1998 where it was given its common name because it became a significant pest of figs.  In 2005, Z. indianus was discovered in Florida and has since been found successively further north and west in the USA (see a map of its distribution here).  It is likely that the North American infestation did not come from the Brazilian population.  Zaprionus indianus is the only member of Zaprionus present in Canada, and therefore the reddish-brown head and thorax and particularly the silvery stripes that extend from the antennae to the tip of scutellum can be used as distinguishing features.

Zaprionis indianus dorsum showing characteristic white stripes

Unlike D. suzukii (thankfully!), female Z. indianus do not possess heavily sclerotized and serrated ovipositors and are not currently seen as a serious threat to temperate fruit crops.  They have been reared from a number of tropical, tree-ripened fruits in Florida and there is concern in vineyards in the eastern USA, where sometimes they outnumber D. suzukii in traps. It is possible that Z. indianus can use fruit that has been oviposited in by D. suzukii, thus increasing damage and possibly complicating control measures.  In Canada, particularly Ontario and Quebec, winter temperatures may preclude establishment of African fig fly, and yearly re-infestation from the south would be necessary for it to show up in future years.  At all but one site, we found just 1-4 flies during late summer and early fall per site, so it will be interesting to see what happens to numbers this coming growing season.  In tropical and sub-tropical locations much larger populations have been detected the year following first detection.

For the past 1.5 years I have been working as a post-doctoral fellow at the University of Guelph with Rebecca Hallett on D. suzukii.  We are developing a push-pull management strategy using volatile plant compounds to repel and attract this pest.  With the occurrence of Z. indianus and possible reoccurrence  in larger numbers in the future, we may have a unique opportunity to study how two recent invaders using similar resources interact, and also, perhaps, a more significant challenge ahead of us  in developing management strategies.  If you are interested in this topic or have current or future experiences with Z. indianus, I and co-authors on the scientific note would appreciate hearing from you.  You can contact me at renkemaj@uoguelph.ca.

—-

Renkema J.M., Miller M., Fraser H., Légaré J.P. & Hallett R.H. (2013). First records of Zaprionus indianus Gupta (Diptera: Drosophilidae) from commercial fruit fields in Ontario and Quebec, Canada, Journal of the Entomological Society of Ontario, 144 125-130. OPEN ACCESS [PDF]

Dick Vockeroth - Chris Borkent
, ,

Dick Vockeroth (1928-2012)

This memorial for Dr. Richard (Dick) Vockeroth is from Dr. Jeff Skevington & Dr. Jeff Cumming of the Diptera Unit at the Canadian National Collection of Insects, Ottawa, Ontario.

—————————

Dick Vockeroth - Chris Borkent

Dick Vockeroth attending the 6th International Congress of Dipterology in Fukuoka, Japan (2006). Photo by Chris Borkent.

The Diptera community has suffered a great loss — Dick Vockeroth passed away on the morning of November 16th 2012, at the age of 84. Almost everyone who studies flies knew Dick, and most of us have some hilarious Vockeroth stories that will undoubtedly continue on for several generations. His breadth of knowledge was unsurpassed and many of us owe him considerably as a mentor. He always amazed us by seeming to know something about virtually every fly species put in front of him. Of course, putting a fly in front of Dick was just the excuse to open the floodgates. For those who could concentrate for long enough, his stories always had a point. They could continue for a long time, but they always wound back to where they started, completing another lesson for those willing to listen. If only we had a way to save all of his immense knowledge. Dick Vockeroth in Churchill ManitobaFortunately, he was always willing to share. He published 120 papers on 27 families of flies over his career. His unpublished manuscripts and keys also fill many boxes in our collection. Copies of many of these are spread around the world with Dick’s colleagues and will ultimately be incorporated and published as part of new studies. In addition to giving freely of his scientific knowledge, Dick was a true philanthropist. He seemed to donate virtually every penny that he had to anyone who stopped at his door or called. He was incredibly frugal with his own purchases and we all benefited/endured from his purchases of cheap (or free) produce and bread that often had seen better days. His immune system seemed to enjoy these nutritional challenges although ours were perhaps not always up to it. We recall a few years ago when Dick had the first cold that he could remember having since he was a child, as well as the first headache in his life a year or two later. Diabetes was his primary health challenge and it was a significant one in his later life. It was likely a contributing factor to the Alzheimer’s that eroded his mind over the last three years.

The following is excerpted from Cumming et al, 2011. This paper is the introduction to a three volume Festschrift in The Canadian Entomologist honouring Dick and the other coordinators of the Manual of Nearctic Diptera. Picking through these papers, you will find some classic stories about Dick and expand your impression of the impact that he played in the Diptera community over the last 60 plus years.

Dick Vockeroth - Japan - CollectingDick was born on May 2nd 1928 in Broderick, Saskatchewan. He received his B.A. and M.A. from the University of Saskatchewan in Saskatoon in 1948 and 1949, respectively, and his D.Phil. on the genera of Scathophagidae from Oxford University in 1954. He officially joined the Canadian National Collection of Insects (CNC) Diptera Unit in 1949. Dick retired in 1991, but contributed broadly to Diptera activities at the CNC as an Honorary Research Associate until 2009. He became a world expert on several families, particularly Mycetophilidae s.l., Dolichopodidae, Syrphidae, Scathophagidae, and Muscidae. He was an avid collector and contributed over 220,000 pinned Diptera to the CNC. Dick authored or co-authored 120 scientific publications, including 12 chapters in the Manual of Nearctic Diptera. He has published 173 new Diptera taxa (1 family group name, 42 genus-group names, and 130 species-group names). Dick was awarded the C.P. Alexander Award in 1997 by the North American Dipterists’ Society. This lifetime award, which can only be held by a single dipterist at a time, publicly acknowledges the most important and influential member of the North American Dipterists’ Society. The Award reads, ‘‘John Richard Vockeroth is recognized as our most knowledgeable dipterist, and for his critical and unique contributions in expanding our knowledge of flies, especially flower flies, educating and encouraging a cadre of world leaders for Systematic Dipterology’’. Sadly, this award is now available to be given to someone else.

Evidence of the respect of Dick’s scientific achievements can be seen in the ninety-one patronyms that have been attributed to him by the entomological community (http://www.canacoll.org/Diptera/Staff/Vockeroth/Vockeroth_Patronyms.pdf). This list will no doubt continue to grow as his collections live on and support new research on the flies that Dick was so passionate about. We have all missed his antics and contributions in the lab since he left in 2009. Let’s hope that we can all leave even a fraction of the lasting legacy and legends that Dick has left behind.
The funeral was held Wednesday 21 November at the Hulse, Playfair & McGarry Chapel at 315 McLeod Street in Ottawa. His obituary appeared in the Ottawa Citizen November 17-19, 2012.

If you wish to make a donation in Dick’s name, he would no doubt be honoured if it went to the Canacoll Foundation (www.canacoll.org), which supports improvements to the CNC by visiting specialists. Cheques made out to the Canacoll Foundation can be sent to the treasurer, Andrew Bennett, at the K.W. Neatby Building, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada. Tax receipts will be issued.

Group of Diptera AwesomeDick Vockeroth and the CNC gangDick Vockeroth, Frank McAlpine and Curtis Sabrosky CNC
Cumming J.M., Sinclair B.J., Brooks S.E., O’Hara J.E. & Skevington J.H. (2011). The history of dipterology at the Canadian National Collection of Insects, with special reference to the Manual of Nearctic Diptera, The Canadian Entomologist, 143 (6) 539-577. DOI:

, ,

Physiology Fridays: Trace-metal phantoms

Living in metal-contaminated lakewater is just another day’s work for phantom midge larvae. 

In the lakes surrounding Sudbury, Ontario and Rouyn-Noranda, Quebec, over 75 years of smelter operations have left their mark by contaminating soil and water with the trace metals cadmium, nickel, copper, and zinc.

This contamination led Maikel Rosabal, Landis Hare, and Peter Campbell, all from the Institut national de la Recherche scientifique in Québec, to study how aquatic animals tolerate these contaminants.  To do so, they needed a study organism that was abundant, easy to collect, and could accumulate and tolerate trace metals.  The best option turned out to be larvae of the phantom midge Chaoborus.

“The lakes in the area, and their watersheds, have been contaminated by the deposition of atmospheric aerosols and particles.  Metal concentrations in lake water tend to be higher in the lakes that are downwind from and close to the smelters, than in lakes that are upwind and distant from the smelter stacks,” says Dr. Peter Campbell. “The presence of Chaoborus in lakes with high metal concentrations implies that they are highly metal tolerant.”

The researchers chose a total of 12 lakes around Sudbury and Rouyn-Noranda with differing concentrations of trace metals, and collected water samples, using diffusion samplers that excluded particles, and midge larvae using a plankton net. After homogenizing the larvae, the researchers used a series of centrifugation, heating, and sodium hydroxide digestion steps to separate the subcellular components of the larvae.  They then measured the amount of metal in each fraction as well as the concentrations of dissolved metals in samples of lake water.  This allowed them to relate the concentrations of each trace metal in lake water to the concentrations in larvae.

They found that the majority of each metal accumulated in the cytosolic heat-stable protein fraction that they isolated from the larvae—a fraction that contains large amounts of metal-binding proteins. And while other fractions also contained small amounts of metals, it was in the heat-stable protein fraction that metal concentrations responded most obviously to the increasing metal concentrations in lake water. This suggests that the Chaoborus larvae were able to bind and detoxify increasingly large amounts of these potentially toxic metals.

“This suggests an important role for these metallothionein-like proteins in the detoxification of metals,” says Dr. Campbell.  “Presumably this contributes to the presence of this insect in highly metal-contaminated lakes.”

While laboratory studies usually focus on the effects of exposure to a single trace metal (usually dissolved in the water), animals in this study were exposed in the field to many trace metals both in the water and in their planktonic food. The researchers suggest that Chaoborus larvae would be effective “sentinels” for estimating trace-metal exposure to lake plankton, which is a key component of ecological risk assessments.

“Rough estimates of trace metal exposure are often obtained by measuring total metal concentrations in the water or the sediment.  Such values usually overestimate metal exposure because much of the metal present is not available for uptake by organisms because they are bound to substances such as organic matter or iron oxides,” explain the researchers. “For these reasons, measurements of trace metals in organisms are increasingly used to estimate exposure in risk assessments.”

Rosabal, M., Hare, L. & Campbell, P.G.C. (2012). Subcellular metal partitioning in larvae of the insect Chaoborus collected along an environmental metal exposure gradient (Cd, Cu, Ni and Zn), Aquatic Toxicology, 120-121 78. DOI: 10.1016/j.aquatox.2012.05.001

Pubmed: http://www.ncbi.nlm.nih.gov/pubmed/22647479

Chaoborus larvae

Photo: Maikel Rosabal

Pollenia griseotomentosa Calliphoridae Cluster fly
, , , ,

CJAI #19 – Cluster flies of North America

Pollenia rudis Face

Pollenia rudis

By Adam Jewiss-Gaines,  a research assistant at Brock University.

———————

When people ask me what the heck a calliphorid is (often after I have mentioned the family name and am being gawked at as if I’m crazy), I usually remark “You know those shiny flies you often see flying around in the spring and summer?”  This isn’t technically 100% accurate since the genus Pollenia, one of the most commonly encountered genera of the family, is in fact non-reflective and grey.  Upon closer inspection, a keen eye can also observe varying amounts of wrinkled, yellow hairs on the thorax.  These two qualities distinguish Pollenia from other blow flies throughout North America.  Despite being a little dull when compared to their more eye-catching iridescent relatives, Pollenia are ecologically important insects as they aid in plant pollination and the processing of various biomaterials.

Pollenia often become particularly active during the spring and summer months once the temperature warms up, although they can occasionally be spotted indoors in the wintertime on a warmer day.  With a sudden onslaught of large, grey insects flying around when the snow begins to melt, it comes as no surprise that people tend to get irritated with them and consider them pests.  Oftentimes they are mistaken as houseflies (Family Muscidae) causing Pollenia species to be labeled as potential food contaminators, but this is not the case.  These insects are also particularly well-known for their clustering behaviour on walls, earning them their common name: cluster flies.

Even though Pollenia are extremely common, their general biology is largely unknown with a few exceptional details. It is known that larval Pollenia are parasites on various other organisms, such as maggots and worms. For example, Rognes (1991) noted that Pollenia pediculata, one of the most common species found throughout the continent, is a parasite of the earthworm species Eisenia rosea. Aside from this little tidbit however, specific information regarding the life cycles of Pollenia species is relatively scarce and further studies in this particular field would greatly improve our knowledge of the genus.

Pollenia griseotomentosa Calliphoridae Cluster fly

Pollenia griseotomentosa

Until very recently it has been thought that all Pollenia found in North America were the same species (Pollenia rudis), but after examining various collections throughout the world, Knut Rognes found that six members of the genus occur throughout the region.  Terry Whitworth adapted much of Rognes’ work shortly thereafter into a nice, clean, simple identification key for North America. With accurate images and photography, however, characters could be even easier to distinguish and observe when one is able to compare a photograph to the creature they have under their microscope.

Therefore, to further expand on Terry’s key and clarify important visual characters, I collaborated with him and Dr. Steve Marshall to create a fully-illustrated digital key for distinguishing the six North American Pollenia species from one another.  Now published in the Canadian Journal of Arthropod Identification, Cluster Flies of North America couples high-resolution images of important traits with a clean and simple interface to create a handy tool to be used by entomologists and non-entomologists alike. If you are relying on this key for identification, it is recommended to use physical specimens of Pollenia rather than images or photos, since even the best of hand-photographs have difficulty capturing key features. In addition, distribution maps are provided for each species, constructed from locality data of specimens from the University of Guelph Insect Collection and Terry Whitworth’s personal collection of Pollenia.

Creating this key has been a great opportunity, and I hope the entomological community is able to make good use of it. My sincere thanks go out to Steve Marshall, Terry Whitworth, the editors, and my labmates and friends for all of their support.

——————————

Jewiss-Gaines, A., Marshall, S.A. & Whitworth, T.L. (2012). Cluster flies (Calliphoridae: Polleniinae: Pollenia) of North America, Canadian Journal of Arthropod Identification, 19 DOI: 10.3752/cjai.2012.19

Rognes, K. 1991. Blowflies (Diptera, Calliphoridae) of Fennoscandia and Denmark. Fauna Entomologica Scandinavica Vol. 24.

ESC Caption C1 P2
, ,

ESC Caption Contest – Cycle 1, Photo 2

We had a great response to last week’s photo, so thank you to everyone who played along. We’ve got an all new photo for you to caption today, but first we need you to vote for your favourite Photo 1 caption.

ESC Caption Contest C1 P1

[polldaddy poll=6409189]

We’ll post the results and award some points next week.

Now, onto this week’s photo (here are the rules if this is your first time):

ESC Caption C1 P2

ESC Caption Contest C1 P2 – Photo by Morgan Jackson

Have fun!