Aves

Brazilian Beauties

A couple of weeks ago my colleague Fabio Akashi Hernandes* from the Universidade Estadual Paulista sent me the file for a poster that I immediately printed on high-gloss paper and proudly affixed to the door of my office. The poster depicts some of the feather mites that Fabio has found on birds from Brazil and a few other tropical countries. Eye candy for acarologists! They are all scaled to the mm mark at bottom right, where you can see the gigantic Laminalloptes phaetontis (Fabricius) from tropicbirds. Among the selected mites are the hoatzin-dwelling Opisthocomacarus umbellifer (Trouessart) (mite #40) in which both sexes are adorned with feather-like setae of unknown function. Typically, though, male feather mites are more elaborate than females. The poster includes species whose males have vicious-looking hind legs (e.g., 1, 28), or are asymmetrical (e.g., 31, 32, 58), or are very well-endowed (20).

Fabio is doing some marvelous work on taxonomy and ecology of these mites, including the very recent discovery of a host-switch from wild cuckoos to domestic poultry. But even though he and his colleague Michel Valim have been working hard to describe new species, at least 80% of bird species in Brazil have yet to be investigated for their acarofauna. Many more wonders await.

Click on the poster image then mouse over and click to magnify.

Fabio's Feather mite poster 6 Oct 2015 sml

*abakashi@gmail.com

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Painless mites

My freezers at work are getting rather full, so I’ve been washing birds and sending the clean bodies to the Royal Alberta Museum. Last week I washed a batch of white-throated sparrows (Zonotrichia albicollis) that had met a sad communal death by flying into a window in Edmonton. They were very mite-rich, providing dozens of specimens of Proctophyllodes (Proctophyllodidae), Mesalgoides (Psoroptoididae), and Analges (Analgidae).  All of these taxa belong to the feather mite superfamily Analgoidea. Analges means “without pain”, and the genus was called thusly by Nitzsch in 1818 because it seemed that even heavily laden birds showed no signs of distress. Almost two hundred years later, a huge comparative study by Ismael Galván and colleagues in 2012 compared feather mite load and host condition of 83 species of birds and found no evidence of a negative relationship. Feather mites in general appear to be harmless commensals of their hosts.

Analges species are interesting because of their striking male polymorphism. All males differ from females in having enlarged third legs with spear-like tarsal claws, but legs of some individuals are much more grotesquely hypertrophied than others. Such males are also larger overall.

White-throated Sparrow Analges compilation lightened

Analges sp. mites from white-throated sparrows from Edmonton, Alberta. From left to right: female, homeomorphic male, heteromorphic male (all to the same scale).

Male polymorphism is very common in feather mites and many other Astigmata. The less elaborated male forms are typically called ‘homeomorphs’ and the extravagant ones ‘heteromorphs’ (the reason for the terms being that the former are more similar to females than the latter).

But what are the modified third legs used for? Holding females? Stabbing rival males? I’m not sure that anyone knows.

White-throated Sparrow Analges male legs

Legs of homeomorphic (left) and heteromorphic (right) male Analges. The pointy tarsal claws look nasty.

 

 

 

 

Snipe hunt

This afternoon one of my colleagues passed on the good news that he had just put a roadkilled charadriiform in the Museum of Zoology’s freezer. I don’t have a lot of mites from Albertan charadriiforms, so I was eager to see get the bird and wash it. The body turned out to be that of a Wilson’s Snipe, currently Gallinago delicata Ord in most taxonomies, though not all feel that it deserved having been raised from its previous subspecies status (G. gallinago delicata).

It was a lovely specimen and I took it to show to people in the main office. “It’s pretty rare to come back from a snipe hunt with an actual snipe!” I said, attempting to be amusing. Two people laughed, and two just stared. “You know what a ‘snipe hunt‘ is, right?” I asked the latter. Nope. When I explained, they got the concept immediately, and came up with other examples (e.g., an apprentice carpenter being sent for a ‘board stretcher’). I wonder if there is an unrecognized linguistic divide in Canada, with snipe-hunting being common in only some regions.

A snipe in the hand.

A snipe in the hand. I washed it after taking the photo and was rewarded with a small number of feather mites and lice.

Diamond Life

In mid-June I spent a week working a at a location farther north than I had ever been – Lac de Gras, 220 km south of the Arctic Circle in the Northwest Territories. On an island in Lac de Gras is Diavik Diamond Mine. Diavik employs about 1000 people to mine and process diamonds and to support the mining operations. The cafeteria is stupendous but the sleeping quarters are not particularly salubrious. It is a dangerous place due to gigantic vehicles, rockfalls, extreme weather and large mammals including caribou and grizzly bears. At Diavik, people are very very safety-conscious.

bad things can happen Diavik trip 12 June 2014 C

Diavik cautionary tale – me beside two heavy equipment tires and the pickup truck they crushed (photo by C. Uherek)

They have made some rather large holes in this island.

Diavik mining pits as seen from helicopter 17 June 2014

Diavik mining pits as seen from helicopter.

To compensate, in part, for their impact on the local environment, Diavik is supporting a number of research and remediation projects on and near the mine, including studies on soil and plants, and on stream fauna. I am involved in the latter via my M.Sc. student Christiane Uherek, whom I cosupervise with Bill Tonn, a fish ecologist in my department. Bill and a half dozen of his students have worked hard over the past several years to create and monitor an artificial stream connecting a previously isolated lake on an island near the mine site with Lac de Gras. The hope is that grayling and other fishes will use this stream to access the lake for breeding.  Christiane isn’t working on the fish directly, but rather on the artificial stream’s physical and biological characteristics. She will compare these features with those of nearby natural streams (references) to determine whether flow, woody debris and invertebrate assemblages of the artificial one fall within the range of variation of natural ones. It’s the macroinvertebrates that connect me to this project.

Reference 6 lake 16 June 2014 sml

Reference 6 Lake, from which Ref 6 Stream 1 flows.

To measure retention of organic matter we tossed artificial sticks and paper ‘leaves’ into streams and measured how far they went downstream before they got stuck.

HP dropping artificial sticks into stream with Chrisitane recording13 June 2014

Me dropping artificial sticks into an artificial stream, with Christiane recording data.

Terrestrial vertebrates (in addition to humans) are surprisingly common at Lac de Gras. Voles, ground squirrels and willow ptarmigan regularly dropped by to check out what we were doing.

male willow ptarmigan West Island stream 15 June 2014 C sml

Male willow ptarmigan wondering why we are measuring sticks.

According to the New Shorter Oxford, ‘ptarmigan’ is a falsely Greekified modification of the original Gaelic name ‘tarmachan’, which means ‘grumbling or croaking’; apt if you listen to the bird’s rather frog-like calls.

During my week there I came to understand why Diavik emphasizes safety with such religious fervour. We experienced lightning storms, rockfall alerts, a vehicle that burst into flames in front of our truck, and a couple of grizzly bears, one of which we escorted with the help of a helicopter from the mine site, across frozen Lac de Gras, to the mainland.

chasing grizzly bear across Lac de Gras with a helicopter 16 June 2014 A

Note to self: grizzly bears can run very fast for a very long time. Fear them.

 

 

 

 

 

Bird wa(tch/sh)ing

Many Canadians go to Mexico to watch birds.  In the vicinity of the UNAM field station at Chamela there is a huge diversity of forest-dwelling, estuarine and marine species. I won’t bore you with my list of twitched birds, but my trip here has allowed me to observe members of several families I’d never previously seen outside of a zoo or a museum (e.g., Cracidae, Fregatidae, Sulidae).

west Mexican chachalacas and magnificent frigatebird compilation

West Mexican Chachalacas (Cracidae) and Magnificent Frigatebird (Fregatidae)

But unlike most avian enthusiasts, as well as watching birds, I also wash them.  Washing the body of a recently deceased host is one of the best ways to get feather mites (Acari: Astigmata: Pterolichoidea and Analgoidea).  While at the station I have ruffled through the feathers of stuffed specimens from their ornithological collection, and was also lucky enough to get to wash a freshly road-killed Buteo magnirostris (Roadside Hawk). The washing yielded feather mites, feather lice, and one hippoboscid fly.  The last has been added to the UNAM Chamela entomological collection, and the others get to come back to Edmonton with me.

washing a Buteo magnirostris roadkilled near UNAM Chamela Feb 2014 sml

The hawk about to be washed.