Monday, October 5, 2015

4-Oct-2015 Brant Lake, New York

Site location. Click to enlarge.
Yes, I arrived at my nephew's wedding last weekend with my spider net.  Because what better way to honor him and his new spouse than by advancing pine cone spider science at their wedding venue?  The towering eastern white pines (Pinus strobus) growing at Jimbo's Club At The Point in the beautiful Adirondack region of New York are one of the features that makes the location so picturesque.  And as I confirmed the day after the wedding, their fallen cones are a microhabitat for spiders.

Lots of fallen cones around the cabins
Fallen P. strobus cones
We had to be packed and away by 11 am, so while others lingered over breakfast conversation, I zipped outside early for a round of morning cone tapping.  The morning was a brisk 50 F at most, but the sun was pleasantly warming, the lake was glittering, and woodpeckers, chickadees, and some very vocal red squirrels (Tamiasciurus hudsonicus) provided a pleasant audioscape.

Erigonine male, only about 1mm long
I tapped 50 cones and got 10 spiders and 2 species as well as one harvestman.  I was able to easily identify the two female Ozyptila praticola (Thomisidae) spiders in my sample since I find them regularly in fallen pine cones here in Seattle, Washington.  The identity of the second species remains to be determined, but is a male linyphiid from the Erigoninae subfamily (right).  The rest of the spiders were juveniles from the families Dictynidae, Linyphiidae (different species from the mature specimen), Philodromidae, and Theridiidae.  I don't find philodromines very frequently in fallen cones, but aside from that this seemed a very typical cone sample.

The state of New York is now on the World Map Of Pine Cone Spiders.

Red maple (Acer rubrum) leaves were transitioning from green to scarlet.

Friday, September 18, 2015

Spiders Cannot Be Identified By Color And Pattern Alone


Atypical Araneus diadematus
female photographed in
Seattle, Washington, USA
Typical appearance of
Araneus diadematus female.
Photo by Friedrich Böhringer
My neighborhood is absolutely festooned with the introduced orb-weaver Araneus diadematus (Araneidae).  By late summer, hardly a shrub or a structure is devoid of one of these orange and brown spiders with the striking white pattern on the dorsum (left).  So I got excited when I spotted a large orange orb-weaver (right) on my balcony that lacked the color and patterning of A. diadematus.  Could a native species of orb-weaver actually be thriving in Seattle, at my house?!

Answer: No, not in this case.

Genitalia of an atypically colored and patterned
Araneus diadematus female from
Seattle, Washington USA.
The spider in question is fairly large (over 0.5 inch long) with distinctive external genitalia, so I was able to identify her with reasonable certainty from a photo (right) as an A. diadematus. (Most species are much too small and/or have genitalia too complex to be identified via photos.)  Despite this spider's exotic appearance, she was just "more of same", albeit atypically colored and patterned.

So, as nice as it would be to identify spiders in the field from easily observable traits like color and pattern, such features aren't necessarily diagnostic and in fact can be misleading.  The only way to identify spiders with certainty is by examining the shape of their genitalia and other tiny, immutable features under a microscope.

Saturday, September 12, 2015

In Search Of Leslie Maurice Cockerell (1872-1943), Collector of Euryopis formosa (Theridiidae) Holotype

Nathan Banks (1908) cited L. M. Cockerell as the
collector of the E. formosa holotype
"By himself, a collector has no sort of scientific value, but he often secures material which may be turned to good account in other hands." ~~ T. D. A. Cockerell

When I was assembling the data presented in How widespread is Euryopis formosa's relationship with pines?, I noticed that Nathan Banks (1908) named L. M. Cockerell as the collector of the E. formosa holotype.  I became curious about the person who collected the first described specimen of a species that has enthralled me for several years.  Who was L. M. Cockerell?  How did this person come to be collecting spiders in Bear, Idaho over 115 years ago, and how did the specimen come to be in the hands of Banks, a prominent entomologist?

My research* revealed that L. M. Cockerell was Leslie Maurice Cockerell, born in Beckenham, County Kent, England in 1872 to Sydney John and Alice Elizabeth (née Bennett) Cockerell.  His siblings included the naturalist and bee expert Theodore Dru Alison "T.D.A." Cockerell (1866–1948), director of the Fitzwilliam Museum Sydney Carlyle Cockerell (1867-1962), book illustrator Olive Juliet Cockerell (1869-1910), book binder Douglas Bennett Cockerell (1870-1945), and actress Una Agnes Cockerell (about 1875-about 1944).

After spending his late teens and early adulthood years in Madeira, eastern Canada and the western United States, Leslie would eventually become a "mining engineer who is representing large English mining interests" in Mexico and then later serve as captain in the British Army "in charge of Mineral Resources Development Department, Ministry of Munitions".  Leslie married Gladys Marguerite [unknown maiden name] (1880-1969) at some date unknown to me, but presumably before the couple set sail together from an American port in 1907.  He died in London, England on 24 April 1943.

Location of Bear, Idaho (click to enlarge)
Unfortunately, the date that Leslie collected the E. formosa holotype in Bear, Idaho went unrecorded by Banks (1908) or by Harvard University's Museum of Comparative Zoology, which currently houses it.  I suspect that Leslie collected the specimen sometime between 1890 and 1894, for the following reasons.

First, letters written between 1887 and 1890 by Leslie's brother T.D.A. Cockerell during his convalescence from tuberculosis in Colorado indicate that Leslie was in Madeira 1887-1888 and eastern Canada 1888-1890, but never traveled to the western United States while T.D.A. was there (Weber, 2004).  In June of 1890, shortly before T.D.A. returned to England, T.D.A. wrote that "Mother's postcard (received today) makes me rather anxious.  It seems Leslie will probably have to come to Colorado.  I must see about this on my return." (p. 550).  Thus, the earliest that Leslie could have been in the western United States was the latter half of 1890.  Second, Leslie was in Colorado by 1892 according to the "May 1891 to April 1892" issue of the journal Nautilus, which published a note from "Leslie M. Cockerell, writing from Norwood, San Miguel Co., Colorado" (p. 83).  Third, in 1894 Nathan Banks described a harvestman that Leslie had also collected in Bear, Idaho.  Assuming that he collected the harvestman and the E. formosa on the same visit to Bear, the 1894 publication provides the closing bracket. Record of Leslie sailing on the ship Anchoria from New York City to Glasgow, Scotland in June, 1895 seems to confirm the end of that particular trip to the United States.

Update (Oct 30, 2015): Leslie Cockerell returned again to Idaho by the latter half of 1898, according to two sources.  A notice in the Sunday, July 31, 1898 issue of Idaho Statesman (Boise) stated: "HOTEL ARRIVALS. Capitol. ... Leslie M. Cockerell, Payette".  Additionally, the University of Colorado Boulder Library archives holds a letter dated December 7, 1898 that Leslie sent from Payette, Idaho to his brother T.D.A. Cockerell.  Payette is located about 50 miles south of Bear.  Thus it is possible that Leslie again visited Bear on this subsequent trip to the American West.

As for why Leslie traveled to the American west, what he experienced there, what impressions it left on him, or even why he collected spiders and how his arachnid specimens ended up in Nathan Banks's collection, those questions remain unanswered.  If Leslie Cockerell left a diary or memoir, I have found no mention of it.  Perhaps letters by Leslie or about him await reading in the archived papers of Nathan Banks (Cambridge, Massachusetts), T.D.A. Cockerell (Boulder, Colorado) or Sydney Carlyle Cockerell (Boston, Massachusetts; London, England; etc.).  Alas, I'm unlikely to visit any of those places anytime soon.  I hope others who are more conveniently located will bring any remaining information to light.  T.D.A. took great delight in young Leslie's "first rate" letters to him (Weber, 2004), so if any survive in archives, they're probably a good read.

As T.D.A.'s quote at the top of the post recognizes, people like Leslie who aren't career scientists but rather "just" science hobbyists, volunteers or assistants play important roles in the advancement of science.  Scientific institutions everywhere are enhanced by their contributions, but they themselves are not memorialized in academic archives or biographies.  Their stories are lost to the history of science.  We should make an effort to remedy that.

Literature Cited

Banks, Nathan. 1894. Washington Phalangida, with description of a new southern Liobunum. The Canadian Entomologist, 26(6):160-164.

Banks, Nathan. 1908. New species of Theridiidae. The Canadian Entomologist 40:205-208.

Weber, William A. (Ed.) 2004.  The Valley of the Second Sons: Letters of Theodore Dru Alison Cockerell, a Young English Naturalist, Writing to His Sweetheart and Her Brother about his life in West Cliff, Wet Mountain Valley, Colorado 1887-1890. Pilgrims Process, Inc., Santa Fe, New Mexico. 592 pages.

*To piece together this story I conducted online Google and Ancestry.com searches, read Trevor Kincaid's correspondence with Nathan Banks and T.D.A. Cockerell, and read The Valley of the Second Sons (Weber, 2004).

Saturday, August 22, 2015

How widespread is Euryopis formosa's relationship with pines?

Click to enlarge. [source]
Rod Crawford and I noted in our recent paper that virtually every Euryopis formosa (Theridiidae) specimen collected in Washington state has been collected in the vicinity of ponderosa pines (Pinus ponderosa) (see map, right).  Our observation was consistent with Gillette et al. (2008), who identified E. formosa as a significant indicator of old-growth status in a pitfall study of the ground-dwelling spiders in P. ponderosa stands in the Cascade Range of California.

Since Euryopis formosa occurs from "Central California north to British Columbia and east to Wyoming" according to Levi (1954), these findings left me wondering whether E. formosa is associated with pines over its entire range, or whether the apparent association is only a Cascades phenomenon.  To begin answering this question, I decided to do a back-of-the-envelope analysis by mapping E. formosa specimen locations reported in Levi (1954) and Bennett at al. (2014) along with those Rod Crawford and I reported on from Washington.

Presence or absence of pine
(Pinus) at E. formosa collection sites
I obtained coordinates for the published locations from USGS's Graphic Names Information System and Google maps, then determined the presence/absence of pines (of any species that drops open, intact cones) in the area using a combination of Google Street View, E-flora B.C. and Calflora.  I mapped the results using GPSVisualizer.  Note that since the specimens listed in Levi (1954) were collected in the late 19th or early 20th century, sometimes from poorly defined locations (e.g. "Jackson County"), I can't be certain that I've correctly identified every location or correctly guessed the forest type growing there at the time of collection.  Hence, "back-of-the-envelope".  Given those caveats, here is the result.  Green markers indicate specimens collected in places where pines were likely to be present at the time of collection.  Collection sites within about 5 miles of pine-containing forests are marked in blue, while sites thought to be devoid of pines are marked in red.

It appears that the spider-pine relationship holds true in the core of E. formosa's range, but less reliably so on the edges. Of course, no firm conclusion can be drawn from this surface analysis.  For that, one would need to get updated specimen data from relevant spider repositories and superimpose it on range maps of pines that drop open, intact cones.  It would be a fair amount of work, but it looks like a worthwhile project.

Friday, August 14, 2015

10-Aug-2015 Lumberman's Monument, Michigan

Site location (click to enlarge)
Red pine forest
Michigan is now on the World Map of Pine Cone Spiders, joining the US states of Washington, Oregon, California and Massachusetts, and the province of South Holland in The Netherlands.  I had the opportunity to tap two species of fallen pine cones at Lumberman's Monument in Michigan's Huron-Manistee National Forests earlier this week, and found spiders in both sets.

Red pine cone
White pine stand
I tapped 50 red pine (Pinus resinosa) cones from the woods near the Monument campground and collected 5 spiders and 1 species.  Fifty tapped eastern white pine (Pinus strobus) cones from a stand near the monument parking lot produced 10 spiders and 2 species, plus 11 harvestmen.  The spiders were from the same families I found to be common in eastern white pine cones in Massachusetts, including Salticidae, Thomisidae, Linyphiidae, Phrurolithidae and Dictynidae.

Eastern white pine cones
Bronze cones are spider habitat too!
Amusingly, I even found that a spider had inhabited the sculpted white pine cone at the foot of the monument's statue. 

The Lumberman's Monument statue depicts a river rat, a
timber cruiser and a sawyer but omits the timber baron
Beautiful red pine bark

Wednesday, August 5, 2015

3-Aug-2015 Green Mountain, Washington

Site locations (click to enlarge)
If ever a mountain lived up to its name, Green Mountain is it.  Emerging from the lowland forest at about 4500 feet (1370 meters) in elevation, hikers on Green Mountain Trail 782 are treated to a spectacular 1.6 mile (2.6 km) wide by half mile high (0.76 km) meadow made green by bracken ferns, at least two species of Rubus, and a variety of flowering herbaceous plants.  Looking southeast across the Siuattle River from the Green Mountain meadows, Washington's most remote volcano, Glacier Peak, is visible shouldering out over Lime Peak.

Small Doug-fir stand in
Green Mtn Pasture
Nobody home
Our first stop of the day was at Green Mountain Pasture at the mountain's base, where I tapped 50 fallen Douglas-fir (Pseudotsuga menziesii) cones from a small stand of trees growing within the pasture.  Although I found an active agelenid web attached to one cone and the occasional spider retreat in others, I found no spiders in the cones.
 
A western white pine cone dwarfs
neighboring Douglas-fir and
western hemlock cones
Its distinctive bark helped me
to locate the parent pine tree
From there a 6 mile drive up the mountainside brought Rod Crawford and me to the Green Mountain trailhead.  Hardly 10 minutes into our hike I spotted a few western white pine (Pinus monticola) cones lying next to the trail and located their source: a single pine tree growing in a forest dominated by western hemlock (Tsuga heterophylla) and Douglas-fir.  But as I've said before, all it takes is one good tree; I had no problem finding 50 fallen pine cones to tap.  From them I collected 12 spiders and 2 species. Two-thirds of the spiders were Cryphoeca exlineae (Hahniidae), a common litter species.  The hemlock cones were so numerous and so much smaller than the pine cones that when I tapped pine cones, a hemlock cone would occasionally fall out.

Green Mountain meadow
A mating pair of grasshoppers
As numerous hikers have noted on the Washington Trails Association's Green Mountain page, the meadow is literally hopping with grasshoppers this time of year.  Each step sets a dozen of them in motion.  Many landed in my net by chance, but never lingered there long enough for me to photograph them.  Only when the air cooled with the setting sun did they slow down enough for portraits.

Pika (Ochotona princeps) on rock
Misumena vatia hunting on
Anaphalis margaritacea
I finally caught up with Rod in a little boulder-strewn draw on the eastern side of the mountain.  He had already sampled conifer litter in a small grove of subalpine trees at its upper end, so I took the opportunity to tap a third set of cones from the same grove.  From 50 tapped mountain hemlock (Tsuga mertensiana) cones I collected exactly zero spiders.  Oh well.  I did enjoy listening to the pikas calling "eep!" while I tapped those empty cones.

Be sure to read Rod's account of the day here!



Sunday, August 2, 2015

31-Jul-2015 Mt Ellinor, Washington

Site location map (click to enlarge)
One way to extend the collecting season into the dry summer months is to collect at ever-higher elevations.  This principle led Rod Crawford, Jessi Bishopp and me to Mt. Ellinor, a popular hiking destination on the Olympic peninsula featuring old-growth forest, panoramic views of the Olympics and Cascades, and mountain goats. The peak was named by 19th century geographer George Davidson in honor of his fiancée Ellinor Fauntleroy, later described by their daughter as a woman whose "knowledge of life and the world made her inclusive rather than exclusive -- an universalist in religion and deed".

Mountain hemlock cone microhabitat
Cryphoeca exlineae female in
mountain hemlock cone
Before reaching the trailhead we stopped to collect a lower elevation sample near Skinwood Creek.  I tapped 50 Douglas-fir (Pseudotsuga menziesii) cones that I found lying next to the road and collected 1 spiderling.  Hiking up into the hemlock-fir forest on the Mt. Ellinor trail I tapped a second set of cones, this time from mountain hemlock (Tsuga mertensiana).  Tapping 50 mountain hemlock cones got me 3 spiders and 1 harvestman.  Two of those spiders were female Cryphoeca exlineae (Agelenidae).  I found each in a web located between cone scales.

Boulder talus on upper Mt. Ellinor
Araneus gemmoides
The ascending trail eventually leaves the closed-canopy forest and skirts a boulder talus field before reaching the peak.  Despite the intense heat in the talus field, I found numerous orb-weaver webs strung up between the stones.  From one of these came what for me was the most striking spider of the day, a melanistic Araneus gemmoides (Araneidae) female.  Usually this species is orangish-brown in color.

Mt Rainier viewed from talus
field on Mt Ellinor
The talus field was as high in elevation as I got, but Jessi bounded on up to the summit with her net.  She apparently did some great spider p.r. while up there because numerous descending hikers smiled and asked whether I was collecting spiders too.  Several stopped to talk, including two energetic little boys who wanted to pick up any spiders that I might have in my net.  It was fun to get so many positive responses when "ew!' is the norm.

Goat hair
Everyone I asked had seen mountain goats along the trail, but much to my disappointment I never did.  However, I did find tufts of goat hair stuck here and there to the vegetation.  This helped me spot goat-made game trails that otherwise I probably wouldn't have noticed.

Read Rod's account of the day here!