Category Archives: Species

Neomolgus littoralis: the red velvet mite

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The video above was taken by Peg 15 on the North Shore of Great Race Rock where the students of a biology class were doing an intertidal transect. We often find Neomolgus at this elevation, and it is one of the few invertebrates inhabiting the top range of the spray zone.

Neomolgus is a tiny mite looking like a little red dot moving across rocks or other hard surfaces. Its diameter is 3mm. Mites are like spiders and ticks in that they have four pairs of legs. At Race Rocks, it is especially common among the bare rocks out on the North West corner by peg15.

Neomolgus has a large distribution in the northern hemisphere. It moves very actively and responds very negatively to the approach of a human finger. It uses its long snout for piercing small flies and sucking their juices.

Links:http://www.beachwatchers.wsu.edu/ezidweb/neomol01.htm

Kozlof : SeashoreLife of the Northern Pacific Coast.

Lamb and Hanby, Marine Life of the Pacific Northwest, page 276

Domain Eukarya
Kingdom Animalia
Phylum Arthropoda
Class arachnida
Order Acari
Trombidiformes
Family Bdellidae
Genus Neomolgus
Species littoralis
Common Name:red velvet mite

 

Other Members of the Phylum Arthropoda at Race Rocks 
taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams.

 March October 2003-  Rahilla (PC)

Myxilla incrustans: incrusting sponge– The Race Rocks Taxonomy

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This sponge can be found on rocky subtidal areas at Race ROcks  It commonly grows over the surface of swimming scallop shells. It is believed to form a mutualistic association with the swimming scallop, obtaining a moveable substrate while preventing predation of the scallop. Apparently the smell of the sponge deters the sea stars which may be intending to prey on the scallop

crustsponge

The volcano-like oscules on the sponge which is attached to the valve of a swimming scallop.

ah052010scallopl

Adam harding took this photo off the docks at Race Rocks. The shell of the scallop is covered with the orangish layer of sponge with attached hydroids.

It is an extremely variable widely distributed species ranging from intertidal to 2540 m
Colour: the colour in life ranges through various shades of gold occasionally to a light gold-brown with a slight tinge of rose. In alcohol the sponge is grey-white to yellowish-brown.
Form: The sponge is incrusting or occasionally massive
Size: Intertidal incrusting forms re up to 8 cm thick an 20 cm in diameter. Dredged massive forms have a diameter of up to 9 cm. Fistules are up to 25 mm high.
Consistency: the consistency is moderately firm and tough. some specimens are weakly spongy and fragile.
Surface: The surface varies from slightly roughened and tuberculate to highly rugose and fistulated. It is somewhat rough to the touch
Oscules: oscules are common or abundant and irregularly distributed. Oscules may be elevated on fistules when the latter are present. Oscules are from 033 to 8 mm in diameter.
Pores: pores are abundant and measure from 20 to 270u in diameter.

 

rmincrustingsponge

Detailed view of the incrusting sponge on a swimming scallop

rmincrusting

Ryan Murphy took this image of the various colours of the sponge

Domain Eukarya
Kingdom Animalia
Phylum Porifera
Class Demospongiae
Order Poecilosclerida
Family Myxillidae
Genus Myxilla
Species incrustans
Common Name: incrusting sponge

 

This file is provided as part of a collaborative effort by the students of Lester B. Pearson College
 Oct 2003 Roberto Ruglio year 30

Phalacrocorax pelagicus: Pelagic cormorant–The Race Rocks Taxonomy

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rmpelagichorm

Pelagic Cormorant,  Phalacrocorax pelagicus photo by Ryan Murphy, 2010

See images of Pelagic Cormorants on Ryan Murphy’s Flickr site

Range of the Pelagic Cormorant:
Breeds from the Bering Sea to Japan and south to near San Diego, USA.  Winters in the Aleutian Islands and along the coast from British Columbia to Baja, California.

Pelagic cormorants nest at Race Rocks and live there year-round. They prefer the cliff to the West of the camera 5, and can often be seen perched there along the cliff edge (picture above left)

Nest:
The nest is a mass of seaweed and grass on a cliff.  Pelagic cormorants nest in colonies and like ledges so narrow they must land and take off facing the cliff. During the years between 1980 and 1995 numbers of nests ranged above 20. In the years 2000, 2001,2002 there was complete nest failure due to the lack of herring feed in the surrounding waters. During 2003 , 2004, and 2005 only two or three nests have been established with successful hatches.

Following  are pictures taken in the nesting season by G.Fletcher in the 1980s and 1990’s when there were pelagic cormorants nesting at Race Rocks:

Local Numbers of Phalacrocorax pelagicus
Xmas bird count

Screen Shot 2014-12-20 at 8.06.55 PM

Pelagic Cormorants–Ryan Murphy photo

Year
1997–14
1998–2
1999–20
2000–14
2001–12
2002–20
2003- no census taken..too stormy!
2004- 110

rmpelagiccorm22010

Pelagic Cormorant–Ryan Murphy photo

 

2005- 20
2006-20
2007-42
2008-storm
2009-90
2010-78
2011-0
2012-0
2013-17
2014—
rmpelagiccorm2010

Pelagic Cormorant–Ryan Murphy photo-2010

Classification:
Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelicaniformes
Family: Phalacrocoracidae
Genus: Phalacrocorax
Species: pelagicus
Common Name: Pelagic cormorant

 

We have seen a marked decline in nesting of one of the four species of seabirds which has nested traditionally at Race Rocks, Pelagic Cormorants (Phalacrocorax pelagicus). By 2007, the nesting population had been reduced to one or two nests, and from 2008 to the last season (2009 ) there were no nests at all. This population crash has been common across the Gulf Islands., and the lower end of Vancouver Island and Strait of Juan de Fuca. According to the Canadian Wildlife Service, the population of this species is estimated to be at 9000 individuals, and the pelagicus subspecies is red-listed by BC – other subspecies are stable.

RM_males-and_female_pelagic_cormornat

Two males and a female pelagic cormorant

In this attached file, I have summarized the results of several papers on research on Cormorant populations in the southern Gulf Islands and Georgia Strait. Vermeer and Rankin, 1984, did their research when the populations were on the incline, however since the 1900s, this trend has not persisted as has been reflected in the paper by Chatwin et al. The summary of their paper and the possible reasons for decline are listed near the end of this review.

See other posts of Pelagic Cormorants at Race Rock

taxonomyiconReturn to the Race Rocks Taxonomy and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams. Garry Fletcher, 2003

 

Arctonoe vittata: Commensal scale worm–The Race Rocks Taxonomy

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scaleworm

Scaleworm on the striped sunstar.( from video)

Physical description: 

The Arctonoe vittata (formerly known as Halosydna lordi) usually have around 25 or more pairs of scale, which they sometimes shed when they are disturbed. Arctonoe grows up to 8cm to 10 cm long and is usually light yellow. However the color may change depending on its host. Scientists do not know wether this is due to a certain compound on the host that changes their color, or wether it is because they basically eat the same thing, but the scale worm usually very lightly changes its color according to its host.

Distribution in the world: Scale worms live in the North Pacific ocean. It is one of the most studied worms and it has been mostly studied near the coasts of Japan and also near Kamtchaka, far east Russia. It also lives in the north west coast of North America, including the coast of British Columbia. It lives mostly in salt water and almost never in fresh water.

Biotic Associations: The Arctonoe vittata a commensal worm, lives on other species. It observes a positive relationship with its host, notably the starfish Asterias amurensis or the mollusc keyhole limpet Diadora aspera It usually lives near the oral part of its host, and when there are two A.vittata there, the other one will live on the arm if it is living on a starfish. The length of the worm is big considering the size of its host, sometimes its ends almost touch when it is curled up on the oral orifice. It mostly likes to live on larger hosts because they are older and more exposed to plankton. If the A.vittata is living on the keyhole limpet, and the keyhole gets attacked by a starfish, the worm will sense that the demise of its host will lead to its own demise. Thus it will bite the seastar’s tube feet and cause it to withdraw. The scale worm is attracted to chemicals released by it’s host. It is interesting to note that the host is also attracted by chemicals released by the commensal worm. The commensal worms seemed to have a different taste for their host depending on which part of the world they came from. However, the limpet Acmaea pallida was the overall favorite host.

Interesting local behavior: Some scale worms have been spotted on seastars. They were colored white, the same as the underside of the star. There have also been some scale worms spotted on sea cucumbers, they were of a reddish color, and were the Red commensal scale worm Arctonoe pulchra

Reproduction and feeding: The A.vittata bites off the food that is left over from the side of the mouth of its host. They are usually fatter if they are located near the mouth of the host. The worms are hermaphrodites. The worm will leave eggs on its host, some grow there, usually the first ones. The rest will move to a different host because there is too much competition with the one that is already there.

Domain Eukarya
Kingdom Animalia
Phylum Annelida
Class Polychaeta
Order polychaetes
Family polynoidae
Genus Arctonoe
Species vittata

Other Annelids at Race Rocks

taxonomyiconReturn to the Race Rocks Taxonomy and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams.  Oct 2003, Lindsay Cheong

with underwater photography of Ryan Murphy

Notoplana acticola: flatworm– The Race Rocks taxonomy

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Notoplana acticola is a polyclad flatworm and it is one of the common polyclads of rocky shores. A specimen may be more than 2cm in length, but the average is about 1cm. We find these occasionally in the mussel beds and under rocks in the lower intertidal.

notoplanaacticola

Some mature Notoplana acticola are sometimes found as hermaphrodites.

Notoplana acticola lives in the upper tide pools and it may be abundant in the lower tide pools as well.

Domain Eukarya
Kingdom animalia
Phylum platyhelminthes
Class turbellaria
Order polycladida
Family otocelid
Genus notoplana
Species  acticola
Common Name:  flatworm
This file is provided as part of a collaborative effort by the students, faculty, staff, and volunteers  of
Lester B. Pearson College
Oct 19, 2003		 Aline Celine

Apodichtys flavidus: The Race Rocks Taxonomy

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These images were taken on the remote camera 5 shows a Pigeon Guillemot prior to feeding a Penpoint gunnel to chicks.During the months of May and June, the Pigeon Guillemots (Cepphus columba) are constantly diving off the north side of Great Race Rock and bringing up penpoint gunnels for their young. They nest under loose rock on several locations arounf the island. They are very cautious about going to their nest burrow where they may be seen by predators,

PUGET SOUND/ Strait of Juan de Fuca SPECIES

Apodichthys flavidus Penpoint Gunnel

Pholis clemensi Longfin Gunnel

Pholis laeta Crescent Gunnel

Pholis ornata Saddleback Gunnel

Pholis schultzi Red Gunnel

Xererpes fucorum Rockweed Gunnel

PENPOINT GUNNEL

This is a family of littoral fishes of the northern Pacific and northern Atlantic.They are typically found hiding under rocks and logs or in tidepools at low tide.The longest gunnel , at maximum of 46 cm,is the Penpoint Gunnel.Most gunnels feed on small crustaceans and molluscs.There are about 14 species, six are found here. Although secretive , this family is common in Puget Sound. This fish is not important commercially and is not considered threatened.This species can breath air when out of water.

PHYSICAL DESCRIPTION: Body elongate and compressed (eel-like body with no pelvic fins). Contains only flexible spines ,may have a dark streak that runs through the eye from top of head downward . Eye round, its diameter about one fifth the into length length of head. It may have small dark spots along the sides.Distance from snout to anal origin greater than half of body length.Maximum length is 1.5 feet.10 large melanophores along dorsal surface of gut and anus, melanophores can be also along postanal and dorsal near caudal region,ventral surface of gut has a row of small melanophores.Colour very variable depending upon diet as well as environment, from green through brown to red, the green colour from pigments dispersed through skin, the red in special pigment cells, the brown in combination (Hart 1973).Teeth are sharp,pointed, apparent in post-larvae.

Dorsal fin KC-XCIV (Miller and Lea 1972).

Anal fin I,36-42 (Miller and Lea 1972); I,38-42 (Hart 1973).

Pectoral fin 15-16 (Hart 1973).

Mouth Terminal,small,with thick lips (Hart 1973).

Verebrae 96-101 (Miller and Lea 1972)

DISTRIBUTION: Southern California to southeast Alaska and Kodiak Island.In British Columbia on both coasts of Vancouver Island, the Strait of Georgia .Common in Burrard Inlet in September.Queen Charlotte Islands (Hart 1973). In costal or bay water blending with vegetation such as Sargassum spp.,Ulva spp., and Zostera spp.,settling on the bottom at ca. mm TL (Wilkie 1966).Pelagic,along coastal waters and bays. Horseshoe Cove and vicinity of Portero Power Plant on San Francisco Bay,Marconi Cove of Tomales Bay.

REPRODUCTION: Spawing occurs from January to March.The egg mass is coiled around by one or both parents.The incubation period is about two and two a half months.Newly hatched larvae average about 13mm, and the body is transparent and positively phototactic (Wilkie 1966).The age of maturity of the penpoint gunnel has not be documented in the literature.Growth appears to be rapid during the first year from 20 to 40 milimeters in April and May to 100 to 120 millimeters by the end of summer.

REFERENCES: J.L.Hart- Pacific Fishes of Canada(1973),Wilkie (1966)

 

 

taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams.

March 8 2003- Miroslav Lestanin

 

Fabia subquadrata: The Pea Crab — The Race Rocks Taxonomy

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Jeremias, Carmen and Felix remove a pea crab from the mantle of a California Mussel.
At Race Rocks there are many large mussels; (up to 30 cm) with such parasite inside.

 

Domain Eukarya
Kingdom Animalia
Phylum Arthropoda
Class Crustacea
Order Decapoda
Family Pinnotheridae
Genus Fabia
Species subquadrata
Common Name:Pea crab

Brief Definition

Pea/Mussel crabs are tiny creatures that live as symbionts, on or in the bodies of other invertebrates (bivalves)

Size

As their common name implies, Pea crabs are small creatures. The female pea crabs are distinctively larger than the male crabs, reachimg a size of 22mm (0.8in). The males however reach a size of 7.3mm (0.3in).

Habitat

Pea crabs occupy 2 different niches during their lifetime. Prior to and after their mating season, the adult female lives in a host. Host species include:

California mussels ( Mytilus californianus )

horse mussels ( Modiolus modiolus ).

Mytilus edulis

As well as other species of bivalves including scallops, oysters, cockles and clams.

The juvenile crabs also occupy a host before they become mature.

Range

These crabs live in mainly the northern hemisphere waters.

Including eastern and western U.S.(Akutan Pass, in the waters of Alaska to Ensenada.), Europe, Argentina and British Columbia, Canada.

It is found in 1 to 3% of California mussels along the central California coast, and 18% of mussels along Vancouver Island, BC, Canada.

Adaptation

Mussel crabs live in specific hosts because each crab responds positively to only certain chemicals that their hosts emit. In this way, they are able to infest the hosts that have the right conditions for them to survive. While in the host, these crabs do not posses an exokeleton. This is beacause the hosts provide them with protection against predators and other harmful external factors. However, when they leave their host to mate in the planktonic environment, the adult crabs grow an exoskeleton to protect their membranous carapace. These crabs also posses 10 legs, of which 2 of them develop into large and powerful claws to help fend off predators when exposed in the plankton, and to also help in the grasping of food.

Relationship with Host

The relationship that exists between the mussel crab and the bivalve is a symbiotic one. The advantage of this relationship is that the crab is protected while it scavenges the necessary nutrients needed by it, in the host. The crab however at times robs its host of a large mount of food and it also feeds off the protective mucus layers that cover the host’s tender tissues.This results in the mussel’s gills been injured. When this occurs the relationship becomes a parasitic one as the crab benefits while the host is affected negatively. Hence they are classified as parasites.

Precautions are taken when animals such as Mya arenaria, Placopecten magellanicus, Argopecten irradians and oysters are sold as to not have a pea crab inside it.

Reproduction and Lifecycle

The pea crabs’ life cycle has two distinct stages. These two stages are so different that in fact they were classified into two different genera.

The first stage comprises of the large, adult females that have soft membranous crapaces. These adults occupy a host each and they produce larvae that mature into the second stage. In the second stage, the offspring (larvae) of the female (that she had produced inside her host) grow up into adults of both sexes.Having reached maturity, they leave their hosts and join swarms in the water to mate. At this stage the pea crabs look more ‘traditional’. They have hard shells, strong legs (for swimming) and at the front of the carapace they have thick hair. Upon completion of mating, the female returns to her host. For a period of 21-25 weeks, she goes through 5 molts before reaching maturity. The female can inhabit here for up to a year, producing larvae from eggs that where fertilised by sperm from her single mating and then the cycle begins again. The mating takes place in late May.

Note: the male after mating dies.

References

Source 1: Pacific Coast Crabs and Shrimps by Gregory.C. Jensen, Ph.D

Source 2: Port Townsend Marine Science Center. Marine & Natural History Exihibits

Source 3: http://www.ptmsc.org/html/peacrabs.html

Source 4: http://life.bio.sunysb.edu/~jmatth/Science.htm

Source 5: http://www.pac.dfo-mpo.gc.ca/sci/shelldis/pages/pcbmu_e.htm

Source 6: http://www.indian-ocean.org/bioinformatics/crabs/crabs/tex1.html

Other Members of the Phylum Arthropoda at Race Rocks 
taxonomyiconReturn to the Race Rocks Taxonomy
and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams.

October 2003-  Michelle(PC)

Pterygophora californica -brown algae- The Race Rocks Taxonomy

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“The number of living creatures of all orders whose existence intimately depends on kelp is wonderful…I can only compare those great aquatic forests…with terrestrial ones in the intertropical regions. Yet if in any country a forest was destroyed, I do not believe nearly so many species would perish as would here from the destruction of kelp”

Thus commented Charles Darwin on kelp. Pterygophora californica commonly known as stalked kelp) which is part of the great kelp family that act as the trees of the oceans. This species is present, amongst other places, at Race Rocks.

BIOTIC ASSOCIATIONS: Ryan Murphy, (PC yr 26) obtained a grant from Mount Allison University in June of 2002 to help him do a project on macroalgae at Race Rocks. In this video below , he captures some of the many epiphytes growing on the perennial Pterygophora californica, a brown algae which grows sub-tidally to a depth of 12 meters at Race Rocks. It is a valuable habitat for the many invertebrates in the subtidal and serves as a buffer to storm surges. From June 2-14 a group of students from Pearson College stayed at Race Rocks for the Johan Ashuvud project. Meet the webcrew here

 

Like other kelp species, this one can mostly be found in subtidal zones. It occurs in subtidal zones mostly up to 12 meters of depth. It is mostly found therefore in subsurface canopies of kelp forests. For this reason it is able to live well around the islands of Race Rocks. The Stalked Kelp grows up to 2 meters in length. It has a straight or gnarled, woody undivided stalk and smooth , strap-like blades extending on opposite sides from the top half of the stalk . The end of the stalk results in a terminal blade with midrib and the stalk develops rings as the years go by similar to those of a tree. Pterygophora is an excellent example of a long -lived perennial seaweed. The blades usually degenerate or wear away in winter and new ones are produced each spring. Often, violent winter storms tear up some of the anchored kelp and deposit it on beaches as in the photo above.

Stalked kelp can reach an age over 17 years. It is possible to find out the exact age of a stalked kelp plant by cutting it down (best to use drift ones that are already detached) and counting the rings in its stalk. At Race Rocks this type of kelp provides habitat for a number of fish and invertebrates and a large community of epiphytic algae.

Domain: Eukarya
Kingdom: Protoctista
Phylum: Phaeophyta
Class: Phaeophyceae
Order: Laminariales
Family: Alariaceae
Genus: Pterygophora
Species: californica (Ruprecht)
Common Name: Stalked Kelp

Description:  This plant has a large stout holdfast of branched root-like structures, and a woody stipe up to 2 m. long and 2 cm. in diameter.  The stipe is terete below and flattened at the apex.  A terminal flat, smooth blade arises from the apex of the stipe; it is linear, 6-10 cm. wide, 60-90 cm. long, and tapers in the attachment region.  Sporophylls are pinnately arranged along the two sides of the flattened portion of the stipe.  The sporophylls are linear, approximately the same shape and size as the terminal blade; up to 20 occur on each side.

Habitat:  On rocks in the upper subtidal zone and down to a depth of about 5 fathoms.

Pacific Coast Distribution:  British Columbia to Mexico.

Reference:
Guide to Common Seaweeds of British Columbia, by R.F Scagel, Printed by K.M Macdonald,1972

pterpile

In the winter storms the woody Pterygophora stipes or stems often end up in drifts on the rocky beach. This photo was taken by G.Fletcher in February 2007.

pterostaranem

The stars on the stipe of Pterygophora were made by a sea urchin grazing. . Photo by Ryan Murphy

oct2011xsectptery

Annual rings in a cross-section of the stipe of Pterygophora : G Fletcher photo
taxonomyiconReturn to the Race Rocks Taxonomy and Image File
pearsonlogo2_f2The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams. -Ryan Murphy  PC yr 26

 

Ralfsia pacifica- brown algae

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Phylum: Phaeophyta
Class: Phaeophyceae
Order: Chordariales
Family: Ralfsiaceae
Ralfsia pacifica (Hollenberg)

Description: This plant forms a flat encrusting layer, firmly attached to the substrate; it is irregularly circular in outline, often lobed at the margin, 2-12 cm. in diameter, 0.5-1.0 cm. thick, and olive brown to black in colour; surface with radial or concentric rings.

Habitat:  On rocks and shells in the middle and lower intertidal zones.

Pacific Coast Distribution:  Alaska to Mexico.

Robert Scagel, 1972

R. pacifica with several rhodophytes in a tide pool

R. pacifica with several rhodophytes in a tide pool

Rhodomelia larix- red algae

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Phylum: Rhodophyta
Class: Rhodophyceae
Order: Ceramiales
Family: Rhodmelaceae
Rhodomela larix (Turner) C. Agardh

Description:  This plant is erect, up to 30 cm. high, brownish black in colour, in clusters, attached to the substrate by a discoid holdfast.  The plant is branched, usually with one or more major cylindrical axes.  The major axes have a profusion of radially arranged cylindrical branchlets, all approximately the same length and unbranched.  At the apices of the branches, evanescent trichoblasts are apparent.

Habitat: On rocks in the intertidal zone.Pacific Coast Distribution: Bering Sea to California
Adapted from Robert Scagel, 1972