Cat's eye comb jelly, sea gooseberry, sea walnut, comb jelly, cat's eye ctenophore • Pleurobrachia bachei
{ctene = comb, phora=bearer}
Left: Cat's eye comb jelly underwater, photo by Teegan Bennington. Right: washed up on shore. They are harder to identify when out of water, but a hand lens, dissecting scope, or a good camera zoom can assist. Photos by Paula Crozier (top) and Maria Shallard (bottom).
Identification
The cat's eye comb jelly is actually a ctenophore, not a jellyfish. It has a small, transparent, round or egg-shaped body, and reaches only 2 cm in diameter. When in water its "combs" or rows of cilia flash a variety of colours. Its two long, retractable tentacles trail behind its body, can be 15 cm long, and may be coloured pink, yellow, white, or brownish. When washed up dead on shore, this creature tends to resemble a transparent marble.
The rainbow of colours created when the rows of cilia beat are sometimes visible in photos, but are better experienced live.
Habitat & Range
This species usually appears in swarms, near the surface of nearshore waters. It is found on the west coast of North America from southern Alaska to northern Mexico.
Similar Species
Other ctenophores have similar colour-flashing cilia, and so that should not be used as a defining characteristic. This is the most common species found in coastal BC waters, however, and its long trailing tentacles and near spherical shape are good identifying features. The similarities it shares with other ctenophore species, some also called sea gooseberries, can be seen in the right-hand video below:
The cat's eye comb jelly is actually a ctenophore, not a jellyfish. It has a small, transparent, round or egg-shaped body, and reaches only 2 cm in diameter. When in water its "combs" or rows of cilia flash a variety of colours. Its two long, retractable tentacles trail behind its body, can be 15 cm long, and may be coloured pink, yellow, white, or brownish. When washed up dead on shore, this creature tends to resemble a transparent marble.
The rainbow of colours created when the rows of cilia beat are sometimes visible in photos, but are better experienced live.
Habitat & Range
This species usually appears in swarms, near the surface of nearshore waters. It is found on the west coast of North America from southern Alaska to northern Mexico.
Similar Species
Other ctenophores have similar colour-flashing cilia, and so that should not be used as a defining characteristic. This is the most common species found in coastal BC waters, however, and its long trailing tentacles and near spherical shape are good identifying features. The similarities it shares with other ctenophore species, some also called sea gooseberries, can be seen in the right-hand video below:
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Human Uses
Ctenophores are often collected for display in aquariums, such as the specimens seen in the above videos from the Vancouver Aquarium.
Intriguing Info
This species preys on copepods, larval fish, eggs, and other creatures that are small enough for it to ingest. It waits for its prey to come to it, with its tentacles and their small side branches (tentillae) extended. When prey comes in contact with the sticky tentacles, they are retracted as the comb jelly swims forward. It manoeuvres its body around to bring the prey close to its mouth.
iNaturalist
https://www.inaturalist.org/taxa/117705-Pleurobrachia-bachei
Ctenophores are often collected for display in aquariums, such as the specimens seen in the above videos from the Vancouver Aquarium.
Intriguing Info
This species preys on copepods, larval fish, eggs, and other creatures that are small enough for it to ingest. It waits for its prey to come to it, with its tentacles and their small side branches (tentillae) extended. When prey comes in contact with the sticky tentacles, they are retracted as the comb jelly swims forward. It manoeuvres its body around to bring the prey close to its mouth.
iNaturalist
https://www.inaturalist.org/taxa/117705-Pleurobrachia-bachei
References
Cowles, D. (2007). Pleurobrachia bachei A. Agassiz, 1860. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed 06/08/2013.
Harbo, R. M. (2011). Whelks to whales: Coastal marine life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P. 71.
Introduction to Ctenophora. University of California Museum of Paleontology, Berkley. Accessed 08/06/2013.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P.112
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2013).
Cowles, D. (2007). Pleurobrachia bachei A. Agassiz, 1860. Invertebrates of the Salish Sea. Rosario Beach Marine Laboratory. Accessed 06/08/2013.
Harbo, R. M. (2011). Whelks to whales: Coastal marine life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P. 71.
Introduction to Ctenophora. University of California Museum of Paleontology, Berkley. Accessed 08/06/2013.
Lamb, A., and Hanby, B. (2005). Marine Life of the Pacific Northwest. Madeira Park, BC: Harbour Publishing. P.112
Authors and editors of page
Kelly Fretwell and Brian Starzomski (2013).