Category Archives: ER Warden Report

Zalophus californianus: California Sea lion–The Race Rocks Taxonomy

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rmuwoct11califswim

California sea lion photo by Ryan Murphy

 

rm2010calsl

Male California sea lion– note ears;

gf15092006calsealion

California sea lion. still wet and therefore almost black. When they are dry they are dark brown. G.Fletcher photo.

California sea lions are known for their intelligence, playfulness, and noisy barking. Their color tends toward chocolate brown, although females are often a lighter golden brown. Males may reach 1,000 lbs. (more often 850 lbs.or 390 kg) and 7 feet (2.1 m) in length. Females grow to 220 lbs. (110 kg) and up to 6 feet (1.8 m) in length. They have a “dog-like” face, and around five years of age, males develop a bony bump on top of their skull called a sagittal crest. The top of a male’s head often gets lighter with age. These members of the Otariid, or walking seal, family have external ear flaps and are equipped with large flippers which they use to “walk” on land.

The trained “seals” in zoos and aquaria are usually California sea lions.

calif

Dry sea lion on the left and wet one on the right with a northern sea lion lying behind them. Sept 2006-G.Fletcher photo

In this picture they are seen mixed in with the Northern Sea Lions on many of the islands at Race Rocks. They do prefer however, West Rock, North Rock and the North West corner and the docks area of Great Race Rocks.

 

bakerlion

Northern and California Sea lion with Mt Baker in the background. photo: G.Fletcher

In 1970 , Trevor Anderson reported to David Hancock for the Journal article “California Sea Lion as a Regular Winter Visitant off the British Columbia Coast” that ” California Sea Lions had hauled out on rocks near the light every winter since 1966…. and a peak of population of 30 was reached in February, 1969.”

It is clear that the population of these animals has risen considerably over the years, and by 2007, up to 300 may haul out in the fall of the year.

rmsept1411slstair

In the fall of 2011, the California sea lions were especially attracted up near the house in mid September . They all departed when an earthquake struck the north end of Vancouver island. Ryan Murphy photo

BREEDING

Sea lions do not pup at Race Rocks, it is strictly a winter haulout colony. Most pups are born on the outer coast to the South in June or July and weigh 13-20 lbs. (6-9 kg). They nurse for at least 5-6 months and sometimes over a year. Mothers recognize pups on crowded rookeries through smell, sight, and vocalizations. Pups also learn to recognize the vocalizations of their mothers. Breeding takes place a few weeks after birth. Males patrol territories and bark almost continuously during the breeding season. Gestation lasts about 50 weeks and lactation 5 to 12 months. The longevity is estimated to be around 17 years.

FEEDING HABITS

California sea lions are opportunistic feeders and eat such things as squid, octopus, herring, rockfish, mackerel, anchovy and whiting. The California sea lion competes with the Northern Sea Lion Eumetopias jubata for habitat and food

NOTES

California sea lions are very social animals, and groups often rest closely packed together at favored haul-out sites on land, or float together on the ocean’s surface in “rafts.” They are sometimes seen porpoising, or jumping out of the water, presumably to speed up their swimming. Sea lions have also been seen “surfing” breaking waves.

The males are probably the most vocal of all mammals, and let out a loud incessant honking bark to protect over their territories. They are faithful to their territories, and to their harems of up to 15 females. Sea Lions swim up to 25mph which makes them one of the fastest aquatic carnivores.

Sea lions are known to damage fishing gear and steal or destroy fish in the nets. As a result a lot of California sea lions drown in nets and they are frequently shot at by commercial fishers.
See examples below and in the video.

Sea lions are preyed upon by killer whales. Sea lions are known to have such diseases as pneumonia, caused by a parasitic lungworm, and a bacterial infection called leptospirosis, which affects their livers and kidneys.

Other problems for California sealions involve humans. Sea lions have been found illegally shot and also caught in drift or gill nets and other marine debris. However, their population is growing steadily, and California sea lions can be seen in many coastal spots

The Californian Sea lion was once killed in great numbers for their blubber which could be made into oil, and the rest would be made into dog food. Today the seal lion is protected by international treaty which has led to a positive shift in their populations.

Domain Eukarya
Phylum: Chordata
Class: Mammalia
Order: Pinnipedia
Family: Otariidae
Genus: Zalophus
Species: californianus
Common Name: California Sea Lion

 ARCHIVED VIDEOS of Sea lions at Race Rocks
sealionimpactsSeptember, 2003 : This past few months we have seen three California and Northern Sea lions with fishing flashers hanging from their mouths. These animals pursue fishing lures , probably especially when live bait is used. They swallow the bait, and take down the meter plus length of leader line before the flasher comes to their mouth. The individuals will be seen for several days trailing these flashers. It is not known whether they eventually shed the flasher or whether this leads to an untimely death. Although they can pick up a flasher in waters at some distance from their haulouts, it certainly makes sense to restrict fishing activity when marine mammals are in the vicinity of a fishing vessel.
slionsFrom August to November, a group of California sea lions hauls out on the shore to the East of the Docks with a few even staying on the docks. They get very used to the boats docking there and are often joined by a few large Northern sea lions as well. The constant barking sound comes from the California Sea lions, and the low growls are from the Northerns.”
lionblastsEffects of DND Blasting at Bentinck Island: On November 7, 2002, the DND were still doing their demolition blasting exercises at Bentinck Island. (not Oct 7 as stated in this draft version of the video) The students from Lester Pearson College who were out for a project week were able to catch the images of the impact of these blasts on the first day from the science centre window and on the second day from the top of the light tower. In the tower, they interviewed Mike Demarchi of LGL who is currently doing a $50,000 contract for the Department of National Defence to monitor the impact of these blasts and to compare them with other disturbances at Race Rocks. ( Click on audio icon below)
ecotourimpactsEcotourism can have both positive and negative effects. In this video, you see twoecotourist whale-watching boats from Victoria B.C. that demonstrate two methods of viewing marine mammals. The yellow boat, the Prince of Whales rounds the middle rock inside the kelp bed, much too close to the island which is covered with northern sea lions and a few California sea lions. Since the animals on the North side of the island do not see the boat coming at this close distance, theyare startled and about 25 of them take to the water. Thehigh profile of the boatis increased by the individuals standing on the top of the boat, probably adding to the scare value.The other boat, the Discovery Launch, comes down the main passage between Great Race and the middle rock. They have approached slowly, drift with the current and present very little impact on both the sea lions on the middle rock and the harbour seals hauled out on the main island down in the foreground. Missing from this video however is video of their departure from the reserve where they swing in very close to the end of the docks, causing a stampede of a dozen sea lions in that areaThere are definite guidelines on viewing distance which are occasionally ignored by commercial operators and by private boats of the public that come into the reserve. Disturbance of any marine mammal colonies by vessel operators is against the law. Every time an animal has to change it’s behaviour because of human behaviour, there is a cost in terms of energy expenditure. Violations of this regulation should be reported to federal fisheries.If you feel you would like to provide feedback on this issue to the Department of Fisheries see contact information in this booklet on their Guidelines
dndblastsDND blasting at Bentinck Island.This video was made on October 7, 2002 in order to document the effect of the Department of National Defence demolition exercises on Bentinck Island on the behaviour of birds and marine mammals at Race Rocks MPA. In previous years we have observed considerable disruption by military exercises involving blasting on nearby Bentinck Island in the fall just after the sea lions have returned to the island. We have requested that blasts be spread out over a longer period of time during an exercise. Traditionally blasts have come in a series of three. The first one would alert the sea lions, the second would send a few in the water and the third would clear the islands. This year on this one occasion, only two blasts were held at five minutes apart. The results are shown in the video.gfsept0809brand849BRANDING:We often encounter marine mammals in the reserve which have been marked when trapped in another location as part of a scientific study. We are including in this file a set of pictures of marine mammals which have been tagged in various studies, along with the particulars of the observations. sealion12ENTANGLEMENT:

In September 1999, this California sealion, with a plastic hoop around his neck, was photographed from the docks at Race Rocks by MPA Guardian Carol Slater.

Sea lion with a plastic ring on his neck.

A sea lion with a plastic ring on his neck. See this file for our posts on “entanglement”. It shows the many examples of human debris compromising the health of sea lions.Sometimes however, there is a good news story. It seems like this California sea lion has made somewhat of a recovery, with skin growing over the plastic. See this and other images by . Ryan Murphy in his Flickr album.

SUBSPECIES

Three subspecies are recognized: Zalophus californianus californianus (Lesson, 1828), Zalophus californianus wollebaeki (Sivertsen, 1953) and Zalophus californianus japonicus (Peters, 1866), each living in a clearly separate range. According to Rice (1998), the differences between these types justifies classification as separate species: Zalophus californianus, Zalophus wollebaeki and Zalophus japonicus

seali2sleep

Ecological Equivalents:  The subspecies Zalophus wollebaeki sea lion from the Galapagos Islands.

 

Other Members of the Class Mammalia 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.

File originally compiled by Caroline Mwaniki (PC yr. 27)

 

Phoca vitulina: Harbour Seal –The Race Rocks Taxonomy

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The total harbour seal population in the eastern north Pacific is estimated to be  330,000, and in California the estimated population was 40,000 in 1997.  They usually are found in small groups, but sometimes occur in numbers of up to 500.
shoulder
RANGE/HABITAT:  Harbour seals are found across the Northern Hemisphere in both the Atlantic and Pacific Oceans.  In the Northeast Pacific, they range from Alaska to Baja California, in Mexico. They favor near-shore coastal waters and frequent sandy beaches, mudflats, bays, and estuaries.

See the most recent posts on harbour seals by the Ecoguardians at Race Rocks 

sealman

Harbour seal photo by Ryan Murphy 2002

silverHarbour seals spend about half their time on land and half in water, and they sometimes sleep in water.  They can dive to 1,500 feet (457 m) for up to 40 minutes, although their average dive lasts 3 to 7 minutes.  They are opportunistic feeders and hunt for sole, flounder, sculpin, hake, cod, herring, octopus, and squid.They will also take fairly large salmon.

This image of a mother an baby harbour seal was taken by Ryan Murphy when he was the Ecoguardian at Race Rocks 2009-2011 See this and many more excellent shots  on his Flickr album of Race Rocks Seals here.rmharbsealandpup

” Ryan and I were doing a live webcast from West Race Rocks, when we came across this harbour seal. It kept returning for a view of our activities so we were able to take several video shots while it hovered nearby. We noticed how it seemed to like returning to this rock pinnacle which was covered with kelp and the plumose anemone. When the lights of the camera get in at close range on the stalks or stipes of the kelp, you can see the brightly colored brooding anemone.” Andras Rozmer, (PC year 26)

 

Birthing location. Mother and and baby harbour seal. A few scenes taken in June at the time of the harbour seals giving birth. Note membranes still attached to the mother in the swimming scenes near the end.

 

Harbour seals are year-round residents of Race Rocks. Their numbers increase to over 400 in June and July at the peak of the pupping season. This video shows a quiet scene with seals hauled out on the shore on the west side of Race Rocks.

 

Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Phocidae
Genus : Phoca
Species : vitulina

Phoca vitulina (Linnaeus, 1758 )

COMMON NAME: Harbour Seal

sealbay

In the summer, the South East bay is often populated by harbour seals. In this view taken in July, 2005 from the tower, you can count at least 25 seals.

southrock

This shot is from the tower of the south bay by PB, Sept. 14 2007, the seals can be seen swimming underwater.

sleeprock

Harbour seals on the south intertidal island, Sept. 2007

sealislandlong

A panorama of the seals on South Islands in June.. photo: GF

sealeaten2

The cause of death of this seal is unknown.It could have been hit by a boat.

sealeaten

It had been providing food for an eagle several days before this picture was taken: see video:

rmsept2009decapsealAt Race Rocks,the Harbour seals are year round residents, although their numbers peak in mid summer to over 400. They have pups on the island from March to July. This file shows what happens if boat traffic is too fast in the ecological reserve or around any seal haulout area,

 

Damion Wilson PC Year 27.
Other Members of the Class Mammalia at Race Rocks.

See the most recent posts on harbour seals by the Ecoguardians 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.

 

Haliotis kamtschatkana: Northern Abalone–The Race Rocks Taxonomy

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Cryptic Coloration of Abalone
Associated organisms with abalone.

Domain Eukarya
Kingdom Animalia
Phylum Mollusca
Class Gastropoda
Subclass Prosobranchia
Order Archaeogastropoda
Suborder Pleurotomariina
Family Haliotidae
Genus Haliotis
Species kamtschatkana
Common Name: Northern Abalone

Paulina and the PC Divers go in search of abalone for our population tagging program. The opportunity arises to demonstrate the escape response of the Northern Abalone, when it is presented with a Pycnopodia, the giant sunflower star.

Scott Wallace did research in 1997 and 1998 at Race Rocks with Pearson College divers. He studied the population dynamics of the Northern Abalone, Haliotis kamtchatkana. His research was done as part of a PhD thesis in Resource Management from the University of British Columbia in Vancouver. In May of 2000, he returned to Race Rocks for a dive with Garry and Hana and an interview with Stephanie Paine and Director Julia Nunes for the Discovery Channel. In this video he demonstrates the measurement technique he used in his research

Link to Abstract of Scott’s Paper
Wallace, Scott, S. 1999, Evaluating the Effects of Three Forms of Marine Reserve on Northern Abalone Populations in British Columbia, Canada. Conservation Biology, Vol 13 No 4, August, 1999, pages 882-887.
An article by Scott Wallace:
Out of Sight, Out of Mind, and Almost out of Time out of sight out of mind–mpa

 

 

 

n 1998, we began a long term research program, initiated by Dr. Scott Wallace, on the population dynamics of the Northern Abalone
(Haliotis kamtschatkana).

For several years, the Pearson College divers monitored the population. In this video, Pearson College graduate Jim Palardy (PC yr.25) explains the process.

Carmen Braden and Garry find a Northern Abalone exposed at low tide in June in the intertidal zone of the east side of Race Rocks. They talk about its adaptations and the problem of overharvesting which has resulted in the endangered status.

This abalone was filmed by Felix Chow as it was rasping off diatoms from the glass wall of the aquarium. A small tongue or radula scrapes the algae from the walls.

General information:

Northern or Pinto abalones (Haliotis kamtschatkana) belong to the class of mollusks having a shell that consists of one piece. The genus they belong to is Haliotis, which means “sea ear” and refers to the flattened shape of the shell.

abaloneshellDescription:

Pintos are the smallest abalones and they are commonly about 4 inches long, however the biggest individuals can grow as big as 6 inches long (12 cm). The shell is oval or rounded with a large dome towards one end; it is also irregularly mottled and narrow. The colour of the shell exterior is mottled greenish brown with scattered white and blue. The shell has a row of respiratory pores through which the abalone takes in water and filters dissolved oxygen from the surrounding water with its gills. Water that passes through the body leaves through the respiratory holes carrying away waster from the digestive system. Pinto abalones have from 3 to 6 open holes in their shells. The shape of these respiratory holes is oval and they are raised. The colour of the pinto abalones’ epipodium is mottled greenish tan or brown. The tentacles are thin and the colour of them can vary from yellowish brown to green. Abalones’ muscular foot has a strong suction power that permits the abalone to clamp tightly to rocky surfaces.

Habitat:

Pinto abalones have definite preferences in locations and habits. Pinto abalones range from Sit ka, Alaska to Monterey, California. The only member of the genus is likely to be found in the Puget Sound region., on the open coast of Vancouver Island and Washington. Farther south pinto abalones become strictly sub tidal. Pinto abalones can be found clinging to rocks in kelp beds along open coastal environments that have a good water circulation. Their habitat is between the low inter tidal zone and sub tidally down to 70 feet (18 meters depth).

Life cycle:

The life cycle of an abalone begins from an egg. Abalone female releases millions of eggs, but only about 1% (or even less) of the offspring survive the many challenges they have to face before maturity. The eggs turn into a free living larva and then after drifting with the currents about a week the abalone larva settles to the bottom and begins to develop the adult shell form.

Predators:

Abalone have many predators. They get eaten by other animals (crabs, lobsters, octopuses, starfish, fish and snails) and crushed to the rocks by strong waves. The sea otter was traditionally one of the most significant predators of abalones, although they have not yet moved into the Strait of Juan de Fuca, from the re-introduction several years ago to northern Vancouver Island.

Nutrition:

Pinto abalones, as all abalones, are herbivores. They use their large, rough radulas (“tongues”) to scrape pieces of algae and other plant material from the rock surfaces. The adult abalone feeds on loose pieces of algae drifting in water. Abalones prefer large brown algae; mainly different kind of kelps and seaweed. The colour banding on many abalone shells is caused by the changes in the type of algae that the abalone has eaten.

Threats:

Pinto abalones used to be subject to sports and commercial fishery . They suffered from over harvesting and habitat loss and poaching. There is now a permanent closure on all abalone fishing on the B.C. Coast. For the Pacific North West Coast First Nations People, the beautiful shells of abalone were used for jewelry and abalone also were a seafood delicacy. They occur sub tidally and only in remote areas.

See the Abalone measurement and statistics exercise at RaceRocks:
http://www.racerocks.com/racerock/research/abalone/abalonemeas.htm

See our abalone exercise for middle school.

References Cited:

Kozloff, Eugene N., Marine Invertebrates of the Pacific Northwest, University of Washington Press, Seattle and London, 1996.

Kozloff, Eugene N., Seashore life of the Northern Pacific Coast, University of Washington Press, Seattle and London, 1996.

Meglitsch, Paul A., Invertebrate Zoology; second edition, Oxford University Press, 1972.

Snively, Gloria, Exploring the Seashore in British Columbia, Washington and Oregon, Gordon Soules Book Publishers Ltd., Vancouver/London, 1981.

http://www.pacificbio.org/ESIN/OtherInvertebrates/NorthernAbalone/NorthernAbalone_pg.html ( available at this URL in 20101)

http://www.sonic.net/~tomgray/describe.html

Other Members of the Phylum Mollusca 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. Salla Vornanen, PC yr 27

 

Haematopus bachmani: Black Oystercatcher–The Race Rocks Taxonomy

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2bloy

Black Oystercatcher, Haematopus bachmani photo by Ryan Murphy

Usually up to 6 pairs of the Black Oystercatcher, Haematopus bachmani nest at Race Rocks . They are also winter residents on the island, with numbers up to 100 individuals at times .

This link will connect you with the log showing the many
entries referring to Haematopus bachmani at Race Rocks.

ryansseton -Black oystercatcher

 

See  Ryan Murphy’s Flickr site for excellent images he took while he was ecoguardian at Race Rocks- 2009-2011

 

bloynest3mAn Oystercatcher nest demonstrates the fine art of camouflage
Classification:
Domain Eukarya
Kingdom Animalia
Phylum Chordata
Subphylum Vertebrate
Class Aves
Subclass Neornithes
Superorder Neognathae
Order Charadriiformes
Suborder Charadrii
Family Haematopodidae
Genus Haematopus
Species bachmani
Common Name :
Black Oystercatcher

Images for this slide show of mating Black oystercatchers were taken on the remote camera 5 by PB. May 29, 2006

This video of the black oystercatcher on the nest in June 2007 was screen-captured from camera 2 which was placed two metres from the nest for the duration of incubation.

June 24, 2007: Hatching day! By the end of the day three chicks are active. This video by Garry Fletcher is a compilation of events throughout the day.

BLOYJune8 -hatch
Link to this post from June 22, 2008 for the hatch of Black Oystercatchers near the boathouse captured from a live webcast on a video camera.

blkoybehav1sSee this video on Black Oystercatcher Behaviour

 

 

 

This post in 2024 has great photos of the chicks of BLOYs

For an interesting article on precocial birds such as these oystercatchers see this link.

The black oyster catcher is a jet black bird with a long red beak and pink legs. They grow to 43-44 cm, relatively large for shorebirds. The male and female adult birds are alike in appearance, but juveniles are dull brown. Race Rocks is home to at least six pairs during early May. The birds leave in early fall and return in later December, in numbers up to 30. In the Race Rocks Christmas bird counts numbers as high as 64 in 1997 have been recorded.

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
64 17 1 25 16 39 storm 16 35 22 0 storm
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
57 32 60 36 30 3 40 — — — — —

The birds often use distracting displays, pretending to have a broken wing or surprising other birds that invade their nests, but are otherwise non-territorial. Both parents incubate two or three eggs on average, and mates may stay together for several years. Locally, since there are no oysters, the bird is not so aptly named, but it does prey upon a variety of intertidal shellfish, including limpets, chitons and various snails. Birds of the same family occupying the same ecological niche are found throughout the shorelines of the world.
Their long, chisel-like beak is perfect for prying the shells open to feed on the soft flesh inside. The skull to the left was the product of predation by a river otter in 2001. The presence of the black oyster catcher nesting areas can be noted upon the discovery of piles of empty shells in the nooks and crannies of Race Rocks. Analysis of the different shells found in these piles has been done and it serves as an indicator of shellfish species diversity on the island, as well as the food web of the oystercatchers.

See the results of the Fall 1999 collection of shells from the midden of the oystercatchers.

Also go to the Lab on the Ecological Niche of the Black Oyster-catcher.

see this Video by Paul Omole of a Black Oystercatcher Feeding. –Sounds of Foghorn in the background .
Other Members of the Class Aves 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.

This file was originally started by Stewart Maudsley, Dec. 2001.

 

Enteroctopus dolpheni: Giant Pacific Octopus: The Race Rocks Taxonomy

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rmoctopus eye

Enteroctopus dolpheni: Giant Pacific Octopus: The advanced eye of a mollusc. Photo by Ryan Murphy

Getting up close and personal was one of the things that former Ecoguardian Ryan Murphy was able to do very well underwater.. Consequently he produced the following interesting images from underwater.

We frequently encounter Octopus while diving at Race Rocks. They blend in very well with the algae and can change colors rapidly. Often the best way to see them is to spot their large (1-2 cm) white suckers in a crevice or cave. According to the website below, “Although it is very unusual to find an individual over 45kg, one large individual captured just near Victoria in 1967 weighed 70 kilograms (156 pounds) and was almost 7.5 meters ( 23 feet ) from arm tip to arm tip.

Smaller animals occur occasionally in low intertidal pools on rocky shores, larger individuals generally subtidal to depths of 100m; along North Pacific rim from northern Asia to California;

One of the largest octopus species known, the largest specimen on record with a total arm spread of 9.6m and a weight of 272 kg; dorsal mantle length usually over 20 cm; weight sometimes exceeding 50 kg; body ovoid, with extensive skin folds, red to reddish brown above, pale below; ocelli absent; arms 3-5 times body length, lacking specialized enlarged suckers and large truncate papillae; hectocotylus large, about one-fifth the length of the third right arm; with 12-15 lamellae on the outer demibranch of each gill; gill lamellae 25-29; ink dark brown; eggs measuring 6-8 mm by 2-3 mm, planktonic larva with a single row of chromatophores on each arm; borne in capsules on long stalks, these entangled and cemented together to form long festoons.

The Giant Pacific Octopus, (Enteroctopus dofleini , Hochberg, 1998) was formerly classified as : Octopus dofleini (Wulker, 1910)

 

Giant Pacific Octopus frequently appear at Race Rocks in the subtidal waters. They are also seen occasionally washed up in the intertidal zone where they contribute to the energy flow of the gulls and eagles. This individual which had died recently in June 2002, became the subject of a webcast and an impromptu dissection on the shore.

Video on Octopus necropsy

Domain: Eukarya
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order Octopoda
Suborder: Incirrata
Family :Octopodidae
Genus: Enteroctopus
Species: dofleini (Hochberg, 1998)
Common Name:  Giant Pacific Octopus
Although E.dofleini has been used extensively in laboratory studies, its natural history is still poorly known. The life cycle is thought to be 4-5 years. Eggs are laid throughout the year, though mainly in the winter, and development takes 5-7 months; hatching peaks in the early spring. The young are pelagic for a short period, probably about 1 month.

The three images above of a baby Octopus were taken in the intertidal zone near the docks by
Ryan Murphy in July 2004.

The adults feed on crustaceans (shrimps and crabs), mollusks (scallops, clams, abalones, moon snails, and small octopuses, and fishes ( rockfishes, flat fishes, and sculpins). Large crabs are stalked and then caught with a sudden flick of one or more arms; empty crab carapaces, shiny shells, and bones often litter the entrance to a lair. The octopus takes smaller shrimps and fishes by slowly arching its body over a seaweed bed, then suddenly pouncing, and enclosing the area in a canopy formed by the web membrane that joins the basal parts of adjacent arms. The sensitive arm tips are then inserted into the impounded area to search for food.

  • Two mesozoan parasites charactersictically occur in the kidneys of E. dofleini: Dicyemennea abreida and Conocyema deca.

This octopus is fed upon by seals, sea otters, dogfish sharks, lingcod, and man. It supports small commercial fisheries in Alaska, Canada, Washington, Oregon, and Northern California. Locally, it is also used by halibut fishers as bait.

Literature Cited:

Robert H. Morris, Donald P. Abbott, and Eugene C. Haderlie, Intertidal Invertebrates of California

Eugene N. Kozloff, Marine Invertebrates of the Pacific Northwest

octopus and diverLink to an assignment on Biodiversity submitted to us by
Shawna Millard Biology 202 at Bellevue Community College, Washington.

 

 

Return to the Race Rocks Taxonomy

This file is provided as part of a collaborative effort by the students, faculty and volunteers of Lester B. Pearson College .  This file was started by: Amanda Muscat PC yr 27, Dec. 2001.

Plankton Lab

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BACKGROUND: Microscopic plankton can be can be collected in a way that allows us to determine densities of the organisms, and therefore compare different pelagic environments. We have already seen how plankton populations can vary from part of the ocean to another. In order to quantify plankton, the following method is suggested. You are urged to come up with your own research problem concerning plankton populations and then proceed to use the following techniques to investigate. Although this lab refers to Pedder Bay on Vancouver Island,, It could be modified to suit any location.

PROCEDURE:

In order to determine densities of organisms, we first have to know the volume of the water from which the sample is taken.

  • You will use a plankton net with a small propellor driven counting log to measure distance travelled in the water that is sampled. To calibrate the log, measure off a distance on the docks, read the dial at the beginning of the trial, drag it through the water the length of the measured section, and the difference in the reading at the end of your tow will be the length of your cylinder of water.
  • Now calculate how many counts on the dial there are per meter.
  • Divide the number of counts per meter into the number of counts through the distance you drag the net for your sample. This gives you a number of meters in length for the sample cylinder.
  • Measure the diameter of the net opening and now calculate the volume of sample taken from the open ocean. The formula for volume of a cylinder is V=(pi X radius squared) X h(meters)

 What is in The sample?

  • Note the total volume of the sample taken. Then remove a representative subsample of 1 ml.
  • Place the 1ml sample in a slide with a measured viewing chamber. Count numbers of individual species in representative quadrats. Obtain the average, and multiply this number by the total number of quadrats available.

 Density determination.

  • .Now calculate the density of the individual species in the sample . i.e. number per cubic cm. then per cubic meter.
  • Calculate the number for a larger area e.g. Pedder Bay ! Hint treat it as a segment of a cone for volume determinations, use a marine chart to determine the measurements of the bay..

Micro-photographs of plankton from Pedder Bay:

Pedder Bay frequently has blooms of Mesodinium rubrum. This organism turns the bay a deep wine colour . It is not a poisonous red tide, but we have noticed that when it is pumped up into seawater tanks, it will easily smother some of the filter feeders such as sponges. Blooms often coincide with nutrient loading followed by a period of sunny weather.

 

Ligia pallasii: Sea Slater –The Race Rocks Taxonomy

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video of sampling of populations of Ligia sp

 

During the Johan Ashuvud project 2004, students explored the intertidal with Garry. They examined various organisms as well as the artificial tidepool.

In this video, we also get a chance to meet all the students taking part in the project

The central part of this video has a section on Ligia sp.

Sexual dimorphism in body proportions is marked in L.pallasii. Males, with their large, laterally expanded ephemeral plates, have a length/width ratio of about 1.6; females and immature males are narrower, with a corresponding ratio of about 2.1. Half- moulted males are occasionally found in which the rear half of the body has moulted and is abruptly significantly wider than as yet unmoulted front half, an odd sight, usually several days after the posterior moult.On the walls of cliffs and sea caves, the larger and broader males often cover and shield the females and juveniles.

L.Pallassi prefers sea cliffs. At Race Rocks, the loose upper intertidal rocks and crevasses on the Western side of the main island provide ideal habitat. There are differences in the osmoregulatory responses shown by these species associated with their behavior and ecology.The slower -moving pallasii lives permanently in cool, moist habitats characterized by fluctuating hypo-saline condition. L.Pallasii are air breathers with gill-like pleopods not equipped with tracheal trees.The respiratory pleopods must be kept moist to function properly.This is done by immersion or by dipping the tail in water in such away that the uropods serve as capillary siphons.

Ligia species are fed upon by birds, especially gulls, and by the intertidal crab. Life span of L.pallasii is 1.5 to 2 years , with breeding occurring in spring and early summer, and the average brood size is 48 plus or minus 11 young.The overall sex ratio is 1:1.

Domain Eukarya
Kingdom Animalia
Phylum or Division Arthropods
Class Crustacea (crustaceans)
Order Isopoda
Family Ligiidae
Genus Ligia
Species pallasii
COMMON NAME:sea slater

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. Dec 2005- Palwasha Hussain Khel

 

Ophiothrix spiculata: Brittle star–The Race Rocks Taxonomy

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Ophiothrix spiculata is a common species among algal holdfasts at Race Rocks. Its arm’s spines are especially long, and each one has a number of small thorns on it. the color is extremely variable but it is generally reddish brown, there may be some orange on the disk, too. in spite of all the color variation, this species is unmistakable because of its thorny spines.

Two sets of video on brittle stars are seen here. They were observed off the docks at Race Rocks in about 10 meters of water. Note the other organisms that live in the area also.

 

This brittle star is lives on the rocky sea floor, from shallow waters to great depths. Brittle stars are related to sea stars. These marine invertebrates move very slowly along the sea bed. More than 2000 species of brittle stars exist in the world.
It has long, thin, spiny arms that radiate from a flat central disk; the arms do not touch each other at their bases. Many of the arms are forked. If a brittle star’s arm is cut off, it will regenerate.
Usually the central disk in these brittle stars is under 2 cm) in diameter. They have an exoskeleton and vary in color. They do not have a brain; they have a simple ring of nerve cells that moves information around the body. Tube feet located along the arms sense light and smells.

This juvenile brittle star was filmed in the lab by Sylvia Roach using a Digital camera attached to a dissecting microscope at 4X

Domain Eukarya
Kingdom Animalia
Phylum Echinodermata
Class Ophiuroidea
Order Ophiurida
Family Ophiodermatidae
Genus Ophiothrix
Species spiculata
COMMON NAME: brittle star

They often gather in large groups and collectively filter food from the circulating water. When roused from a hiding spot their best form of defense is to crawl away-

The projections on the five arms of this brittle star look like many tiny hairs, but are actually spines. That being said, they are gentle, very delicate creatures that do not harm humans. They are nocturnal (feed and move about primarily at night); they stretch out to catch food particles, passing the bits down to the central mouth.
To avoid predation, if a predator catches one of its legs, it has the ability to swim off, leaving that leg behind, and it can regenerate a new one!

Waving arms point out the home of the stars. Those aren’t worms, they’re brittle stars, sea star cousins that hide themselves under rocks and in the holdfasts of kelp, especially in the Pterophyga at Race Rocks.

For comparison with another species, see this image in our ecological equivalents file an image of a large 20cm species from the Galapagos:

 

 

 

Reference Cited:

Eugena N. Kozloff , Seashore Life of the North Pacific Coast

http://www.mbayaq.org/efc/living_species/default.asp?hOri=1&inhab=142

 

Other Members of the Phylum Echinodermata 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)

Leptasterias hexactis The Race Rocks Taxonomy

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The six rayed sea star is found both intertidally and subtidally at Race Rocks. They are one of the smaller sea stars.

Domain Eukarya
Kingdom Animalia
Phylum Echinodermata
Class Asteroidea
Order Forcipulatida
Family Asteriidae
Genus Leptasterias
Species  hexactis  (Stimpson,1862)
COMMON NAME: Six- rayed Star
Introduction
Description: Radius 2″ (51 mm), 6-armed ( note the species name hexactis referring to the six arms.). Green, black, brown, or red, sometimes mottled. Disk moderate-sized with 6 fairly broad arms; spines on upper surface dense and mushroom-shaped. rarely do we find these at Race Rocks exceeding 15 cm in length.
Habitat: On rocky shores. We frequently find these when doing intertidal studies or when diving in shallow water at Race Rocks. Range British Columbia to s. California.
Discussion: L. hexactis eats small snails, limpets, mussels, chitons, barnacles, sea cucumbers, and other species, including dead animals. It produces yellow, yolky eggs that stick together in a mass after fertilization. These are brooded under the disk of the female until they hatch as miniature sea stars after 6 to 8 weeks. The small six-rayed sea stars of the West Coast are quite variable and have presented problems of identification. The only other species currently recognized is the Small Slender Sea Star (L. pusilla) which has sharp spines and longer, thinner arms than L. hexactis, and is a light gray-brown or reddish color. It also has a very limited range from San Francisco to Monterey Bay. It reaches a radius of 1″ (25 mm).
Echinoderms have a few important aspects in common. They have bony ossicles in their body. They have a water-vascular system which pumps water through the madroporite. They also have small jaws that are supported by the water-vascular system. And they have tube feet which they use to attach to objects, for protection, as well as to obtain food. They have radial symmetry and most can regenerate lost limbs.

 

Other Members of the Phylum Echinodermata 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.

 December 2001(PC)

Mediaster aequalis: Vermillion star–The Race Rocks Taxonomy

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Mediaster in its habitat. Photo by Dr.A..Svoboda

Snail predation

 

Vermillion stars are seen frequently by divers in the 0-15 meter depth at Race Rocks.

 

Information.
Bright red (vermillion in fact) with large plates along its five arms. To 20 cm. Common just below the surface on low tides but hardly ever high and dry. These are abundant subtidally – you may find plenty after storms or extreme tides.

This Vermillion star male was emitting sperm while in the tank at Pearson College in early January 2004 . This went on for more than three hours. Millions of sperm are broadcast into the water where they may have a chance encounter with eggs which are simultaneously released into the current by the females. Of the great numbers of eggs and sperm released only a few are fertilized and actually make it to maturity. This is a good example of
r-selection in the population.

– http://www.wavelengthmagazine.com/1998/jj98neigh.htm

Mediaster aequalis is one of the smaller sea stars ranging in size from three to seven inches. It is found on many types of beaches at very low tides.

– http://www.geocities.com/oscmarinetech/Animals.htm#Vermillion%20Star

The vermillion sea star is common in shallow subtidal waters. Its feeding area stretches to nearly the tip of each arm on the underside. The vermillion star, so named because of its colour can be found from the Alaskan Peninsula, south to southern Caifornia.

Colour: Vermillion aborally, more orange orally; tube feet red to flesh colour.

Habitat: common on rocks shell, sand, gravel, pebbles and mud.

Feeding: diet varies with substrate and season; eats encrustin sponges and bryozoans on ock; seapen.

Reproduction: breeds from March to May; number of eggs in 65mm sea star estimated at 1,800 per year. the eggs measure 1 to 1.2mm and are bright opaqe orange. It is estimated that Vermillion sea stars reach sexual maturity within four years.

Speed: The sea star can move anywhere between 27 and 40 cm per minute.

Reference: The Sea Stars of British Columbia, Lambert, 1981, British Columbia Provincial Museum, Victoria

Other Members of the Phylum Echinodermata 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.

Dec 2001 Damien Guihen (PC yr 27)