Showing posts with label species. Show all posts
Showing posts with label species. Show all posts

Sunday, March 31, 2024

CANADA'S GREAT BEARS

Look at how this protective mamma bear holds her cub in her arms to give him a bit of a wash. 

Her gentle maternal care is truly touching. This mamma has spent late Autumn to Spring in a cave, having birthed them while still hibernation and staying in the den to feed them on her milk.

Black bear cubs stay with their mamma for the first one to three years of their lives while she protects them and teaches them how to thrive in the wild using their keen sense of smell, hearing, vision and strength. Once they are old enough, they will head off into the forest to live solo until they are ready to mate and start a family of their own. 

Mating is a summer affair with bears socializing shoulder to shoulder with potential mates. Once they have mated, black bears head off on their own again to forage and put on weight for their winter hibernation. If the black bear lives in the northern extent of their range, hibernation lasts longer — they will stay in their dens for seven to eight months longer than their southern counterparts. For those that enjoy the warmer climes in the south, hibernation is shorter. If food is available year-round, the bears do not hibernate at all.

The American black bear, Ursus americanus, is native to North America and found in Canada and the United States. 

They are the most common and widely distributed of the three bear species found in Canada. 

There are roughly 650,000 roaming our forests, swamps and streams — meaning there is a good chance of running into them if you spend any amount of time in the wild. 

Full-grown, these fuzzy monkeys will be able to run 48 kilometres (30 miles)  an hour and smell food up to 32 kilometres (20 miles) away.

With their excellent hearing, black bears usually know you are near well before you realize the same and generally take care to avoid you. Those that come in contact with humans often tend to want to check our garbage and hiking supplies for tasty snacks — hey, a free meal is a free meal.    

In British Columbia, we share our province with nearly half of all black bears and grizzly bears that reside in Canada. The 120,000 - 150,000 black bears who live in the province keep our Conservation Officers busy. They account for 14,000 - 25,000 of the calls the service receives each year. Most of those calls centre around their curiosity for the tasty smells emanating from our garbage. They are omnivores with vegetation making up 80-85% of their diet, but they are flexible around that — berries and seeds, salmon or Doritos — bears eat it all. 

And, as with all wild animals, diet is regional. In Labrador, the local black bear population lives mostly on caribou, rodents and voles. In the Pacific Northwest, salmon and other fish form a large part of the protein in their diet versus the bees, yellow jackets and honey others prefer. The braver of their number have been known to hunt elk, deer and moose calves — and a few showy bears have taken on adults of these large mammals. 

Bears hold a special place within our culture and in First Nation mythology in particular — celebrated in art, dance and song. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, the word for black bear is t̕ła'yimother is a̱bas and łaxwa̱lap̓a means to love each other

Kermode or Spirit Bear, Ursus americanus kermodei
From the photos here you can see that black bears are not always black —  ranging in colour from cinnamon to brown, tan, blonde, red — and even white. 

The Kermode or Spirit Bear, Ursus americanus kermodei, a subspecies of black bear found only in British Columbia — and our official provincial mammal — is a distinctive creamy white. 

They are not albinos, their colouring stems from a recessive mutant gene — meaning that if they receive two copies it triggers a single, nonsynonymous nucleotide substitution that halts all melanin production. Well, not all. They have pigmented eyes and skin but no colour in their fur. The white colour is an advantage when you are hunting salmon by day. Salmon will shy away from their black cousins knowing their intention is to enjoy them as a tasty snack. 

Spirit Bears live in the Great Bear Rainforest on British Columbia's north and central coast alongside the Kitasoo/Xai’xais First Nation who call the Kermode moskgm’ol or white bear.

The Kitasoo/Xai’xais have a legend that tells of Goo-wee, Raven making one in every ten black bears white to remind us of the time glaciers blanketed the land then slowly retreated — their thaw giving rise to the bounty we harvest today.  

Black bears of any colour are a wee bit smaller than their brown bear or grizzly bear cousins, with males weighing in at 45 to 400 kilograms (100 to 900 pounds) and females ranging from 38 to 225 kilograms (85 to 500 pounds). 

Small by relative standards but still very large animals. And they are long-lived or at least can be. Bears in captivity can live up to 30 years but those who dwell in our forests tend to live half as long or less from a mixture of local hazards and humans. 

Reference: Wild Safe BC: https://wildsafebc.com/species/black-bear/


Tuesday, December 6, 2022

OYSTER: T'LOX'TLOX

One of the now rare species of oysters in the Pacific Northwest is the Olympia oyster, Ostrea lurida, (Carpenter, 1864).  

While rare today, these are British Columbia’s only native oyster. 

Had you been dining on their brethren in the 1800s or earlier, it would have been this species you were consuming. Middens from Port Hardy to California are built from Ostrea lurida.

These wonderful invertebrates bare their souls with every bite. Have they lived in cold water, deep beneath the sea, protected from the sun's rays and heat? Are they the rough and tumble beach denizens whose thick shells tell us of a life spent withstanding the relentless pounding of the sea? Is the oyster in your mouth thin and slimy having just done the nasty—spurred by the warming waters of Spring? 

Is this oyster a local or was it shipped to your current local and, if asked, would greet you with "Kon'nichiwa?" Not if the beauty on your plate is indeed Ostrea lurida

Oyster in Kwak'wala is t̕łox̱t̕łox̱
We have been cultivating, indeed maximizing the influx of invasive species to the cold waters of the Salish Sea for many years. 

But in the wild waters off the coast of British Columbia is the last natural abundant habitat of the tasty Ostrea lurida in the pristine waters of  Nootka Sound. 

The area is home to the Nuu-chah-nulth First Nations who have consumed this species boiled or steamed for thousands of years. Here these ancient oysters not only survive but thrive — building reefs and providing habitat for crab, anemones and small marine animals. 

Oysters are in the family Ostreidae — the true oysters. Their lineage evolved in the Early Triassic — 251 - 247 million years ago. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest and my family, an oyster is known as t̕łox̱t̕łox̱

I am curious to learn if any of the Nuu-chah-nulth have a different word for an oyster. If you happen to know, I would be grateful to learn.

Friday, September 2, 2022

FOSSIL FLORA AND FAUNA OF MADAGASCAR

Aioloceras besairiei (Collingnon, 1949)
A stunning example of the internal suturing with calcite infill in this sliced Aioloceras besairiei (Collingnon, 1949) ammonite from the Upper Cretaceous (Lower Albian) Boeny region of Madagascar. 

This island country is 400 kilometres off the coast of East Africa in the Indian Ocean and a wonderful place to explore off the beaten track.

Madagascar has some of the most spectacular of all the fossil specimens I have ever seen. This beauty is no exception. The shell has a generally small umbilicus, arched to acute venter, and typically at some growth stage, falcoid ribs that spring in pairs from umbilical tubercles, usually disappearing on the outer whorls. I had originally had this specimen marked as a Cleoniceras besairiei, except Cleoniceras and Grycia are not present in Madagascar. 

This lovely, seen in cross-section, is now far from home and in the collection of a wonderful friend. It is an especially lovely example of the ammonite, Aioloceras besairiei, making it a beudanticeratinae. Cleoniceras and Grycia are the boreal genera. If you'd like to see (or argue) the rationale on the name, consider reading Riccardi and Medina's riveting work from back in 2002, or Collingnon from 1949.

The beauty you see here measures in at a whopping 22 cm, so quite a handful. This specimen is from the youngest or uppermost subdivision of the Lower Cretaceous. I'd originally thought this locality was older, but dating reveals it to be from the Lower Albian, so approximately 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma.

Aioloceras are found in the Cretaceous of Madagascar at geo coordinates 16.5° S, 45.9° E: paleo-coordinates 40.5° S, 29.3° E.; and in four localities in South Africa: at locality 36, near the Mzinene River at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E. 

We find them near the Mziene River, at a second locality north of Hluhluwe where the Mzinene Formation overlies the Aptian-Albian Makatini Formation at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E; and at Haughton Z18, on the Pongola River in the Albian III, Tegoceras mosense beds at 27.3° S, 32.2° E: paleo-coordinates 48.0° S, 7.8° E.

If you happen to be trekking to Madagascar, know that it's big. It’s 592,800 square kilometres (or  226,917 square miles), making it the fourth-largest island on the planet — bigger than Spain, Thailand, Sweden and Germany. The island has an interesting geologic history.

Although there has been a geological survey, which was active extending back well into French colonial times, in the non-French-speaking world our geological understanding of the island is still a bit of a mystery. 

Plate tectonic theory had its beginnings in 1915 when Alfred Wegener proposed his theory of "continental drift." 

Wegener proposed that the continents ploughed through the crust of ocean basins, which would explain why the outlines of many coastlines (like South America and Africa) look like they fit together like a puzzle. Half a century after Wegener there is still no agreement as to whether in continental reconstructions Madagascar should be placed adjacent to the Tanzanian coast to the north (e.g., McElhinny and Embleton,1976), against the Mozambique-Natal coast (Flores 1970), or basically left where it is (Kent 1974, Nairn 1978).

There have been few attempts apart from McKinley’s (1960) comparison of the Karoo succession of southwestern Tanzania with that of Madagascar to follow the famous geological precept of “going to sea.” One critical reason is that although there may be a bibliography of several thousand items dealing with Madagascan geology as Besairie (1971) claims, they are items not generally available to the general public. The vital information gained of the geology of the offshore area by post-World War II petroleum exploration has remained largely proprietary. 

Without this data to draw upon, our understanding remains incomplete. I don't actually mind a bit of a mystery here. It is interesting to speculate on how these geologic puzzle pieces fit together and wait for the big reveal. Still, we have good old Besairie from his 1971, Geologie de Madagascar, and a later précis (Besairie, 1973).

We do know that Madagascar was carved off from the African-South American landmass early on. The prehistoric breakup of the supercontinent Gondwana separated the Madagascar–Antarctica–India landmass from the Africa–South America landmass around 135 million years ago. Madagascar later split from India about 88 million years ago, during the Late Cretaceous, so the native plants and animals on the island evolved in relative isolation. 

It is a green and lush island country with more than its fair share of excellent fossil exposures. Along the length of the eastern coast runs a narrow and steep escarpment containing much of the island's remaining tropical lowland forest. If you could look beneath this lush canopy, you'd see rocks of the Precambrian age stretching from the east coast all the way to the centre of the island. The western edge is made up of sedimentary rock from the Carboniferous to the Quaternary.

Red-Tailed Lemurs, Waiwai & Hedgehog
Madagascar is a biodiversity hotspot. Just as Darwin's finches on the Galápagos were isolated, evolving into distinct species (hello, adaptive radiation), over 90% of the wildlife from Madagascar is found nowhere else. 

The island's diverse ecosystems, like so many on this planet, are threatened by Earth's most deadly species, homo sapien sapiens. 

We arrived back in 490 CE and have been chopping down trees and eating our way through the island's tastier populations ever since. Still, they have cuties like this Red-Tailed Lemur. Awe, right?

Today, beautiful outcrops of wonderfully preserved fossil marine fauna hold appeal for me. The material you see from Madagascar is distinctive — and prolific.

Culturally, you'll see a French influence permeating the language, architecture and legal process. There is a part of me that pictures these lovely Lemurs chatting away in French. "Ah, la vache! Regarde le beau fossile, Hérissonne!"

We see the French influence because good 'ol France invaded sleepy Madagascar back in 1883, during the first Franco-Hova War. Malagasy (the local Madagascarian residents) were enlisted as troops, fighting for France in World War I.  During the Second World War, the island was the site of the Battle of Madagascar between the Vichy government and the British. By then, the Malagasy had had quite enough of colonization and after many hiccuping attempts, reached full independence in 1960. Colonization had ended but the tourist barrage had just begun. You can't stop progress.

If you're interested in learning more about this species, check out the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). R.C. Moore (ed). Geological Soc of America and Univ. Kansas Press (1957), p L394. Or head over to look at the 2002 paper from Riccardi and Medina. 2002. Riccardi, A., C. & Medina, F., A. The Beudanticeratinae and Cleoniceratinae (Ammonitina) from the Lower Albian of Patagonia in Revue de Paléobiologie - 21(1) - Muséum d’Histoire Naturelle de la ville de Genève, p 313-314 (=Aioloceras besairiei (COLLIGNON, 1949). You have Bertrand Matrion to thank for the naming correction. Good to have friends in geeky places!

Collignon, M., 1933, Fossiles cenomaniens d’Antmahavelona (Province d’ Analalave, Madagascar), Ann. Geol. Serv. Min. Madagascar, III, 1934 Les Cephalopods du Trias inferieur de Madagascar, Ann. Paleont. XXII 3 and 4, XXII 1.

Besairie, H., 1971, Geologie de Madagascar, 1. Les terrains sedimentaires, Ann. Geol. Madagascar, 35, p. 463.

J. Boast A. and E. M. Nairn collaborated on a chapter in An Outline of the Geology of Madagascar, that is very readable and cites most of the available geologic research papers. It is an excellent place to begin a paleo exploration of the island.

If you happen to parle français, check out: Madagascar ammonites: http://www.ammonites.fr/Geo/Madagascar.htm

Thursday, July 28, 2022

FOSSIL AMMONOIDS OF NEVADA

Time Slows at Berlin-Ichthyosaur State Park
Around half past five, as the first flush of dawn appears, our group was up and ready to visit a site that has been on my bucket list for some time.

High on the hillside up a long entry road sits the entrance to Berlin-Ichthyosaur State Park in central Nevada. It is a short 2-hour drive from our lodgings through orange-hued grasslands and low sloping hills.

A worn American flag and sun-bleached outbuildings greet you on your way to the outcrops. Away from the hustle and bustle that defines the rest of Nevada this place feels remarkably serene. Your eyes squint against the sun as you search for ammonoids and other marine fossil fauna while your nose tends to the assault from the bracing smell of sagebrush.

This site holds many stories. The interpretive centre displays wonderful marine reptiles, ichthyosaurs in situ, as you might expect from the name of the park — but it also showcases years of history lovingly tended. This stretch of dry golden low hills dappled with the yellow of creosote and desert grasses is an important locality for our understanding of the Carnian-Norian boundary (CNB) in North America.

The area is known worldwide as one of the most important ichthyosaur Fossil-Lagerstätte because of the sheer volume of remarkably well-preserved, fully articulated (all the sweet bones laid out all in a row...) specimens of Shonisaurus popularis.

Rich ammonoid faunas outcrop in the barren hills of the Upper Triassic (Early Norian, Kerri zone), Luning Formation, West Union Canyon, Nevada. They were studied by N. J. Silberling (1959) and provide support for the definition of the Schucherti and Macrolobatus zones of the latest Carnian — which are here overlain by well-preserved faunas of the earliest Norian Kerri Zone. 

The genus Gonionotites, very common in the Tethys and British Columbia, is for the moment, unknown in Nevada. The Upper Carnian faunas are dominated by Tropitidae, while Juvavitidae are conspicuously lacking. 

Middle Triassic Ammonoids
Despite its importance, no further investigations had been done at this site for a good 50 years. That changed in 2010 when Jim Haggart, Mike Orchard and Paul Smith — all local Vancouverites — collaborated on a project that took them down to Nevada to look at the conodonts and ammonoids. They did a bed-by-bed sampling of ammonoids and conodonts in West Union Canyon during October of that year.

October is an ideal time to do fieldwork in this area. There are a few good weeks between screaming hot and frigid cold. It is also tarantula breeding season so keep your eyes peeled. Those sweet little burrows you see are not from rodents but rather largish arachnids. 

The eastern side of the canyon provides the best record of the Macrolobatus Zone, which is represented by several beds yielding ammonoids of the Tropites group, together with Anatropites div. sp. 

Conodont faunas from both these and higher beds are dominated by ornate metapolygnthids that would formerly have been collectively referred to Metapolygnathus primitius, a species long known to straddle the CNB. Within this lower part of the section, they resemble forms that have been separated as Metapolygnathus mersinensis. Slightly higher, forms close to Epigondolella' orchardi and a single Orchardella n. sp. occur. This association can be correlated with the latest Carnian in British Columbia.

Higher in the section, the ammonoid fauna shows a sudden change and is dominated by Tropithisbites. Few tens of metres above, but slightly below the first occurrence of Norian ammonoids Guembelites jandianus and Stikinoceras, two new species of conodonts (Gen et sp. nov. A and B) appear that also occur close to the favoured Carnian/Norian boundary at Black Bear Ridge, British Columbia. Stratigraphically higher collections continue to be dominated by forms close to M. mersinensis and E. orchardi after BC's own Mike Orchard.

The best exposure of the Kerri Zone is on the western side of the West Union Canyon. Ammonoids, dominated by Guembelites and Stikinoceras div. sp., have been collected from several fossil-bearing levels. Conodont faunas replicate those of the east section. The collected ammonoids fit perfectly well with the faunas described by Silberling in 1959, but they differ somewhat from coeval faunas of the Tethys and Canada. 

The ammonoid fauna paints a compelling picture of Tethyan influence with a series of smoking guns. We see an abundance of Tropitidae in the Carnian, a lack of Pterosirenites in the Norian, copious Guembelites, the Tethyan species G. philostrati, the stratigraphic position of G. clavatus and the rare occurrence of Gonionotites. Their hallelujah moment was likely finding an undescribed species of the thin-shelled bivalve Halobia similar to Halobia beyrichi — the clincher that perhaps seals this deal on Tethyan influence. 

I'll take a boo to see what Christopher McRoberts published on the find. A jolly good idea to have him on this expedition as it would have been easy to overlook if the focus remained solely on the conodonts and ammonoids. McRoberts has published on the much-studied Pardonet Formation up in the Willison Lake Area of Northeastern, British Columbia. He knows a thing or two about Upper Triassic Bivalvia and the correlation to coeval faunas elsewhere in the North American Cordillera, and to the Boreal, Panthalassan and Tethyan faunal realms. 

If you fancy a read, they published a paper: "Towards the definition of the Carnian/Norian Boundary: New data on Ammonoids and Conodonts from central Nevada," which you can find in the proceedings of the 21st Canadian Paleontology Conference; by Haggart, J W (ed.); Smith, P L (ed.); Canadian Paleontology Conference Proceedings no. 9, 2011 p. 9-10.

Fig. 1. Location map of Berlin-Ichthyosaur State Park

Marco Balini, James Jenks, Riccardo Martin, Christopher McRoberts, along with Mike Orchard and Norman Siberling, did a bed by bed sampling in 2013 and published on The Carnian/Norian boundary succession at Berlin-Ichthyosaur State Park (Upper Triassic, central Nevada, USA) and published in January 2014 in Paläontologische Zeitschrift 89:399–433. That work is available for download from ResearchGate. The original is in German, but there is a translation available.

After years of reading about the correlation between British Columbia and Nevada, I had the very great pleasure of walking through these same sections in October 2019 with members of the Vancouver Paleontological Society and Vancouver Island Palaeontological Society. It was with that same crew that I'd originally explored fossil sites in the Canadian Rockies in the early 2000s. Those early trips led to paper after paper and the exciting revelations that inspired our Nevada adventure.

If you plan your own adventure, you'll want to keep an eye out for some of the other modern fauna — mountain lions, snakes, lizards, scorpions, wolves, coyotes, foxes, ground squirrels, rabbits, falcons, hawks, eagles, bobcats, sheep, deer and pronghorns.

Figure One: Location map of Berlin-Ichthyosaur State Park. A detailed road log with access information for this locality is provided in Lucas et al. (2007).

Wednesday, March 30, 2022

URSUS NURSERY: BLACK BEARS / TLA'YI

Look at how this protective mamma bear holds her cub in her arms to give him a bit of a wash. 

Her gentle maternal care is truly touching. This mamma has spent late Autumn to Spring in a cave, having birthed them while still hibernation and staying in the den to feed them on her milk.

Black bear cubs stay with their mamma for the first one to three years of their lives while she protects them and teaches them how to thrive in the wild using their keen sense of smell, hearing, vision and strength. Once they are old enough, they will head off into the forest to live solo until they are ready to mate and start a family of their own. 

Mating is a summer affair with bears socializing shoulder to shoulder with potential mates. Once they have mated, black bears head off on their own again to forage and put on weight for their winter hibernation. If the black bear lives in the northern extent of their range, hibernation lasts longer — they will stay in their dens for seven to eight months longer than their southern counterparts. For those that enjoy the warmer climes in the south, hibernation is shorter. If food is available year-round, the bears do not hibernate at all.

The American black bear, Ursus americanus, is native to North America and found in Canada and the United States. 

They are the most common and widely distributed of the three bear species found in Canada. 

There are roughly 650,000 roaming our forests, swamps and streams — meaning there is a good chance of running into them if you spend any amount of time in the wild. 

Full-grown, these fuzzy monkeys will be able to run 48 kilometres (30 miles)  an hour and smell food up to 32 kilometres (20 miles) away.

With their excellent hearing, black bears usually know you are near well before you realize the same and generally take care to avoid you. Those that come in contact with humans often tend to want to check our garbage and hiking supplies for tasty snacks — hey, a free meal is a free meal.    

In British Columbia, we share our province with nearly half of all black bears and grizzly bears that reside in Canada. The 120,000 - 150,000 black bears who live in the province keep our Conservation Officers busy. They account for 14,000 - 25,000 of the calls the service receives each year. Most of those calls centre around their curiosity for the tasty smells emanating from our garbage. They are omnivores with vegetation making up 80-85% of their diet, but they are flexible around that — berries and seeds, salmon or Doritos — bears eat it all. 

And, as with all wild animals, diet is regional. In Labrador, the local black bear population lives mostly on caribou, rodents and voles. In the Pacific Northwest, salmon and other fish form a large part of the protein in their diet versus the bees, yellow jackets and honey others prefer. The braver of their number have been known to hunt elk, deer and moose calves — and a few showy bears have taken on adults of these large mammals. 

Bears hold a special place within our culture and in First Nation mythology in particular — celebrated in art, dance and song. In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, the word for black bear is t̕ła'yimother is a̱bas and łaxwa̱lap̓a means to love each other

Kermode or Spirit Bear, Ursus americanus kermodei
From the photos here you can see that black bears are not always black —  ranging in colour from cinnamon to brown, tan, blonde, red — and even white. 

The Kermode or Spirit Bear, Ursus americanus kermodei, a subspecies of black bear found only in British Columbia — and our official provincial mammal — is a distinctive creamy white. 

They are not albinos, their colouring stems from a recessive mutant gene — meaning that if they receive two copies it triggers a single, nonsynonymous nucleotide substitution that halts all melanin production. Well, not all. They have pigmented eyes and skin but no colour in their fur. The white colour is an advantage when you are hunting salmon by day. Salmon will shy away from their black cousins knowing their intention is to enjoy them as a tasty snack. 

Spirit Bears live in the Great Bear Rainforest on British Columbia's north and central coast alongside the Kitasoo/Xai’xais First Nation who call the Kermode moskgm’ol or white bear.

The Kitasoo/Xai’xais have a legend that tells of Goo-wee, Raven making one in every ten black bears white to remind us of the time glaciers blanketed the land then slowly retreated — their thaw giving rise to the bounty we harvest today.  

Black bears of any colour are a wee bit smaller than their brown bear or grizzly bear cousins, with males weighing in at 45 to 400 kilograms (100 to 900 pounds) and females ranging from 38 to 225 kilograms (85 to 500 pounds). 

Small by relative standards but still very large animals. And they are long-lived or at least can be. Bears in captivity can live up to 30 years but those who dwell in our forests tend to live half as long or less from a mixture of local hazards and humans. 

Reference: Wild Safe BC: https://wildsafebc.com/species/black-bear/


Wednesday, March 9, 2022

SQUIRRELS: SHADOW TAILS

One of the little animals I see daily in Kitsilano, Vancouver, are the very busy, highly comic rodents we know as squirrels. 

They spend their days busily gathering and caching food and their nights resting from all that hard work. 

My neighbourhood has mostly Eastern Gray squirrels, Sciurus carolinensis (Gmelin, 1788) who come in a colour palette of reddish-brown, grey (British spelling) and black. 

These cuties have bushy tails and a spring in their step — racing around gathering nuts, finding secret hiding spots to cache them, teasing dogs and generally exuding cuteness.

We find the first fossil evidence of tree squirrels in the Pleistocene. At least twenty specimens have been found of Sciurus carolinensis in Pleistocene outcrops in Florida on the eastern coast of the United States. Over time, their body size grew larger then shrunk down to the 400 to 600 g (14 to 21 oz) weight we see them today.  

Eastern Gray squirrels have two breeding seasons in December-January and June-July. This year has been unseasonably warm. On Vancouver Island, the Eastern Grays bred again in early September. One wonders if the heat dome killed off the July litter, and with the return of more favourable weather, the parents have been induced to breed again.

While they are not native to Vancouver, they are plentiful. They were introduced to the region over a hundred years ago and have been happily multiplying year upon year. 

Our native species are the smaller, reddish-brown, rather shy Douglas squirrels, Tamiasciurus douglasii (Bachman, 1839), and the nocturnal Northern Flying Squirrels, Glaucomys sabrinus (Shaw, 1801).  

Sciurus, is derived from two Greek words, skia, meaning shadow, and oura, meaning tail. The name choice is poetic, alluding to squirrels sitting in the shadow of their tails. 

The specific epithet, carolinensis, refers to the Carolinas on the eastern seaboard of the United States, an area that includes both North and South Carolina. It was here that the species was first recorded and still rather common. In the United Kingdom and Canada, Sciurus carolinensis is referred to as the Eastern Gray or grey squirrel — and though adorable is an invasive species. 

In the United States, Eastern is used to differentiate the species from the Western Gray or Silver-Gray squirrel, Sciurus griseus, (Ord, 1818). 

The Ord here, of course, is George Ord, the American zoologist who named the species based on notes recorded by Lewis and Clark in the early 1800s. If you fancy a read, check out his article from 1815, "Zoology of North America." It is charming, anachronistic and the first systemic zoology of America by an American. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, use the word ta̱minasux̱, to express: "that is a squirrel." 

The word for shadow in Kwak'wala is gagumas and tail is ha̱t̕sa̱x̱ste' — so I will think of these wee wonders of the Order Rodentia in the family Sciuridae as the Gagumas ha̱t̕sa̱x̱ste' of Khahtsahlano. 

Wednesday, August 25, 2021

SHORE CRAB: CARCINUS MAENAS / KU'MIS

European Green Shore Crab / Carcinus maenas
The adaptable European Green Shore Crab, Carcinus maenas, lives in a wide range of environments from fully marine to brackish estuaries.

In the Kwak'wala language of the Kwakiutl First Nations of the Pacific Northwest, this brave fellow is ḵ̓u'mis — and in Norwegian, he is called krabbe.

They make a living off the seafloor, dining on worms, molluscs, small crustaceans and any number of bits and pieces that fall their way.

Shore Crabs are euryhaline, meaning they can tolerate a wide range of salinities (4 to 52 %), and survive in temperatures of zero to 30 °C (32 to 86 °F). This adaptability gives them a very wide range and competitive edge. This fellow is from the chilly waters of central Norway. The ability to eat pretty near anything and survive in extremely cold climates means he'll do quite well beneath the ice this winter.

Tuesday, August 17, 2021

AMMONITE: INDEX FOSSILS AS TIME KEEPERS

Argonauticeras besairei, José Juárez Ruiz
An exceptional example of the fractal building of an ammonite septum, in this clytoceratid Argonauticeras besairei from the awesome José Juárez Ruiz.

Ammonites were predatory, squidlike creatures that lived inside coil-shaped shells.

Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. 

They used these tentacles to snare prey, — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunt today.

Catching a fish with your hands is no easy feat, as I am sure you know. But the Ammonites were skilled and successful hunters. They caught their prey while swimming and floating in the water column. 

Within their shells, they had a number of chambers, called septa, filled with gas or fluid that were interconnected by a wee air tube. By pushing air in or out, they were able to control their buoyancy in the water column.

They lived in the last chamber of their shells, continuously building new shell material as they grew. As each new chamber was added, the squid-like body of the ammonite would move down to occupy the final outside chamber.

They were a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. 

These molluscs, commonly referred to as ammonites, are more closely related to living coleoids — octopuses, squid, and cuttlefish) than they are to shelled nautiloids such as the living Nautilus species.

The Ammonoidea can be divided into six orders:

  • Agoniatitida, Lower Devonian - Middle Devonian
  • Clymeniida, Upper Devonian
  • Goniatitida, Middle Devonian - Upper Permian
  • Prolecanitida, Upper Devonian - Upper Triassic
  • Ceratitida, Upper Permian - Upper Triassic
  • Ammonitida, Lower Jurassic - Upper Cretaceous

Ammonites have intricate and complex patterns on their shells called sutures. The suture patterns differ across species and tell us what time period the ammonite is from. If they are geometric with numerous undivided lobes and saddles and eight lobes around the conch, we refer to their pattern as goniatitic, a characteristic of Paleozoic ammonites.

If they are ceratitic with lobes that have subdivided tips; giving them a saw-toothed appearance and rounded undivided saddles, they are likely Triassic. For some lovely Triassic ammonites, take a look at the specimens that come out of Hallstatt, Austria and from the outcrops in the Humboldt Mountains of Nevada.

Hoplites bennettiana (Sowby, 1826) Christophe Marot
If they have lobes and saddles that are fluted, with rounded subdivisions instead of saw-toothed, they are likely Jurassic or Cretaceous. If you'd like to see a particularly beautiful Lower Jurassic ammonite, take a peek at Apodoceras. Wonderful ridging in that species.

One of my favourite Cretaceous ammonites is the ammonite, Hoplites bennettiana (Sowby, 1826). This beauty is from Albian deposits near Carrière de Courcelles, Villemoyenne, near la région de Troyes (Aube) Champagne in northeastern France.

At the time that this fellow was swimming in our oceans, ankylosaurs were strolling about Mongolia and stomping through the foliage in Utah, Kansas and Texas. Bony fish were swimming over what would become the strata making up Canada, the Czech Republic and Australia. Cartilaginous fish were prowling the western interior seaway of North America and a strange extinct herbivorous mammal, Eobaatar, was snuffling through Mongolia, Spain and England.

In some classifications, these are left as suborders, included in only three orders: Goniatitida, Ceratitida, and Ammonitida. Once you get to know them, ammonites in their various shapes and suturing patterns make it much easier to date an ammonite and the rock formation where it is found.

Ammonites first appeared about 240 million years ago, though they descended from straight-shelled cephalopods called bacrites that date back to the Devonian, about 415 million years ago, and the last species vanished in the Cretaceous–Paleogene extinction event.

They were prolific breeders that evolved rapidly. If you could cast a fishing line into our ancient seas, it is likely that you would hook an ammonite, not a fish. They were prolific back in the day, living (and sometimes dying) in schools in oceans around the globe. We find ammonite fossils (and plenty of them) in sedimentary rock from all over the world.

In some cases, we find rock beds where we can see evidence of a new species that evolved, lived and died out in such a short time span that we can walk through time, following the course of evolution using ammonites as a window into the past.

For this reason, they make excellent index fossils. An index fossil is a species that allows us to link a particular rock formation, layered in time with a particular species or genus found there. 

Generally, deeper is older, so we use the sedimentary layers of rock to match up to specific geologic time periods, rather like the way we use tree rings to date trees. A handy way to compare fossils and date strata across the globe.

References: Inoue, S., Kondo, S. Suture pattern formation in ammonites and the unknown rear mantle structure. Sci Rep 6, 33689 (2016). https://doi.org/10.1038/srep33689

https://www.nature.com/articles/srep33689?fbclid=IwAR1BhBrDqhv8LDjqF60EXdfLR7wPE4zDivwGORTUEgCd2GghD5W7KOfg6Co#citeas

Photos: Argonauticeras besairei from the awesome José Juárez Ruiz.

Photo: Hoplites bennettiana from near Troyes, France. Collection de Christophe Marot

Thursday, August 12, 2021

PLAYFUL WATERBABIES: PORPOISE

Dall's Porpoise
These delightfully friendly and super smart fellows are Dall's porpoise. 

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, a blowhole is known as a ka̱'was, whether on a dolphin (porpoise) or whale and a porpoise is known as a k̓ulut̕a

In the Pacific Northwest, we see many of their kind — the shy, blunt-nosed harbour porpoise, the social and herd-minded Pacific white-sided dolphin and the showy and social Dall's porpoise.  

Of these, the Dall's porpoise is a particular favourite. These speedy muscular black and white showboats like to ride the bow waves of passing boats — something they clearly enjoy and a thrill for everyone on board the vessel. If you slow down, they will often whisk away, but give them a chance to race you and they may stay with you all afternoon. 

Harbour porpoises are the complete opposite. You are much more likely to see their solid black bodies and wee fin skimming through the waves across the bay as they try to avoid you entirely. Harbour porpoise prefer quiet sheltered shorelines, often exploring solo or in small groups of two or three. 

We sometimes see these lovely marine mammals represented in the art of the First Nations in the Pacific Northwest, particularly along the coast of British Columbia. You will know them from their rather rectangular artistic depiction with a pronounced snout and lacking teeth (though they have them) used to portray killer whales or orca. 

As a group, even considering the shy Harbour porpoise, these marine mammals are social and playful. Humpback whales are fond of them and you will sometimes see them hanging out altogether in the bays and inlets or near the shore. 

They are quite vocal, making lots of distinctive and interesting noises in the water. They squeak, squawk and use body language — leaping from the water while snapping their jaws and slapping their tails on the surface. They love to blow bubbles, will swim right up to you for a kiss and cuddle. 

Each individual has a signature sound, a whistle that is uniquely their own. They use these whistles to tell one of their friends and family members from another.

Porpoise are marine mammals that live in our world's oceans. If it is salty and cold, you can be pretty sure they are there. They breathe air at the surface, similar to humans, using their lungs and inhaling and exhaling through a blowhole at the top of their heads instead of through their snouts.