Wikipedia

Pacific sanddab

The Pacific sanddab (Citharichthys sordidus), also known as the soft flounder, mottle sanddab, or megrim, is a fish species in the order Pleuronectiformes, or flatfish.[1] It is by far the most common sanddab, and it shares its habitat with the longfin sanddab (C. xanthostigma) and the speckled sanddab (C. stigmaeus). The adult Pacific sanddab is bilaterally asymmetrical and ‘left-eyed’, meaning both eyes are located on the left side of its body.[2]

Pacific sanddab
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Carangiformes
Family: Paralichthyidae
Genus: Citharichthys
Species:
C. sordidus
Binomial name
Citharichthys sordidus
(Girard, 1854)
Synonyms

Psettichthys sordidus Girard, 1854

It is a medium-sized flatfish, with a light brown color mottled brown or black on its eyed side, occasionally with white or orange spots.[3] On its blind side, it is a solid white or light brown. It has large eyes and scales, and a deep rounded body.[1]

Distribution

edit

The Pacific sanddab is endemic to the East Pacific Ocean, from the Bering Sea to Baja California.[1] They are most commonly found at depths of 50 to 150 m (160 to 490 ft), though the young inhabit shallower waters, occasionally moving into tide pools.

 
A map of Pacific sanddab distribution, shading indicating that it is found along the coast of Alaska down to Baja California.

Biology

edit

The Pacific sanddab is an opportunistic predator, feeding on a variety of crustaceans, as well as smaller fish, squid, and octopuses. Their diet has been known to include anchovies, fish eggs, sea squirts, shrimp, crabs, and marine worms.[1]

Due to their abundance in coastal ecosystems, Pacific sanddabs have an important ecological role, providing food for various predators such as marine mammals, birds, and fish. They comprise a significant part of some breeding seabird diets, such as the Brandt’s cormorant and Pigeon guillemot, the latter of which may be considered a sanddab specialist.[4] Fish predators include salmon, skates, lingcod, Pacific sablefish and larger flatfish.[5]

Like all flatfish, the Pacific sanddab begins life as a bilaterally symmetrical fish larva,[2] a stage which lasts for up to 271 days.[6] As the larva matures, its right eye migrates over its head to the left side of its body. During this process, it shifts from a pelagic to a benthic lifestyle and begins to exhibit its characteristic side-swimming behavior. The fish also undergoes changes to its circulatory, nervous, and musculoskeletal system during this process.[2][1]

Their unique eye placement is an adaptation which makes them suitable for this bottom-dwelling lifestyle, allowing them to use both eyes for detection while buried or laying along the sea floor. Additionally, by swimming close to the bottom, the Pacific sanddab and other flatfishes are able to move more efficiently and conserve energy using the ground effect.[7] They also take advantage of the substrate at the bottom by burying themselves to hide from predators, a behavior that is facilitated through their flattened body shape.[7]

The Pacific sanddab exhibits sexual dimorphism, with adult females growing to a larger size than males.[5]

The Pacific sanddab is oviparous and can reproduce multiple times in one spawning season. The spawning season takes place from July through September or October off the coast of Southern and Central California.[8][9] Populations at higher latitudes show a shift in spawning season; in Puget Sound off the coast of Washington spawning occurs from February to May.[10]

Conservation

edit

The Pacific sanddab is currently classified as a species of least concern by the IUCN.[11]

It is a popular game fish in northern California, found on menus in the Monterey Bay and San Francisco area, though more difficult to find in southern California restaurants and markets. Usually sold frozen, some regard it as a delicacy. It is also popular in restaurants and stores along the coasts of Oregon and Washington, where it can be found more readily.[citation needed]

As Pacific sanddabs have a rapid growth rate coupled with early maturation, their vulnerability to overfishing is believed to be relatively low.[12] However, females appear to be maturing at significantly smaller sizes when comparing data from 2016 to data from 1951.[13] This decrease in size of mature females is most likely due to commercial fishing activity,[14] although there is evidence that warmer ocean temperatures have contributed to similar decreasing size trends in other groundfish such as haddock and North Sea plaice.[15][16][17] Larger females tend to produce a higher quantity and quality of offspring,[18] thus this increase in proportion of smaller mature females may have a negative impact on the species population.

References

edit
  1. ^ a b c d e Barss, William H. The Pacific Sanddab. Oregon Department of Fish and Wildlife, March 1976.
  2. ^ a b c Moyle, Peter B. (2004). Fishes: An Introduction to Ichthyology (5th ed.). Pearson Prentice Hall.
  3. ^ Froese, Rainer; Pauly, Daniel (eds.). "Citharichthys sordidus". FishBase. September 2006 version.
  4. ^ Ainley, David G.; Boekelheide, Robert J., eds. (1990). Seabirds of the Farallon Islands: ecology, dynamics, and structure of an upwelling-system community. Stanford, Calif: Stanford University Press. ISBN 978-0-8047-1530-0.
  5. ^ a b Lefebvre, Lyndsey. (2013). Status of the U.S. Pacific sanddab resource in 2013. Pacific Fishery Management Council, Portland, OR.
  6. ^ Ralph, Larson, & Sakuma, K.M. (2008). Distribution of pelagic metamorphic-stage sanddabs Citharichthys sordidus and C . stigmaeus within areas of upwelling off central California.
  7. ^ a b Gibson, Robin N.; Stoner, Allan W.; Ryer, Clifford H. (2014-12-08), Gibson, Robin N.; Nash, Richard D.M.; Geffen, Audrey J.; van der Veer, Henk W. (eds.), "The behaviour of flatfishes", Flatfishes (1 ed.), Wiley, pp. 314–345, doi:10.1002/9781118501153.ch12, ISBN 978-1-118-50119-1, retrieved 2024-11-14
  8. ^ "Fatigue behaviour and life predictions of a particle-reinforced metal matrix composite at room and elevated temperaturesOgarevic, V.V. Diss. Abstr. Int. (May 1993) 53 (11) ISSN: 0419–4217". International Journal of Fatigue. 16 (5): 360. July 1994. doi:10.1016/0142-1123(94)90277-1. ISSN 0142-1123.
  9. ^ Arora, H.L. 1951. An investigation of the California sand dab, Citharichthys sordidus (Girard). Calif. Fish and Game. 37:3-42.
  10. ^ Ureña, H. M. 1989. Distribution of the eggs and larvae of some flatfishes (Pleuronectiformes) off Washington, Oregon and Northern California, 1980-1983. MS thesis Oregon State University. 207p.
  11. ^ Munroe, T.A., Amaoka, K., Matsuura, K. & Carpenter, K.E. 2021. Citharichthys sordidus. The IUCN Red List of Threatened Species 2021: e.T158620855A158623825. https://dx.doi.org/10.2305/IUCN.UK.2021-3.RLTS.T158620855A158623825.en. Accessed on 14 November 2024.
  12. ^ Cope, Jason M.; DeVore, John; Dick, E. J.; Ames, Kelly; Budrick, John; Erickson, Daniel L.; Grebel, Joanna; Hanshew, Gretchen; Jones, Robert; Mattes, Lynn; Niles, Corey; Williams, Sarah (August 2011). "An Approach to Defining Stock Complexes for U.S. West Coast Groundfishes Using Vulnerabilities and Ecological Distributions". North American Journal of Fisheries Management. 31 (4): 589–604. doi:10.1080/02755947.2011.591264. ISSN 0275-5947.
  13. ^ Lefebvre, Lyndsey S.; Payne, Amber M.; Field, John C. (2016-01-01). "Reproductive dynamics of Pacific sanddab, Citharichthys sordidus, off the central coast of California". Journal of Sea Research. Proceedings of the Ninth International Symposium on Flatfish Ecology. 107: 100–111. doi:10.1016/j.seares.2015.07.003. ISSN 1385-1101.
  14. ^ Jørgensen, Christian; Enberg, Katja; Dunlop, Erin S.; Arlinghaus, Robert; Boukal, David S.; Brander, Keith; Ernande, Bruno; Gårdmark, Anna G.; Johnston, Fiona; Matsumura, Shuichi; Pardoe, Heidi; Raab, Kristina; Silva, Alexandra; Vainikka, Anssi; Dieckmann, Ulf (2007-11-23). "Ecology: Managing Evolving Fish Stocks". Science. 318 (5854): 1247–1248. doi:10.1126/science.1148089. ISSN 0036-8075.
  15. ^ Grift, R. E.; Rijnsdorp, A. D.; Barot, S.; Heino, M.; Dieckmann, U. (2003-08-07). "Fisheries-induced trends in reaction norms for maturation in North Sea plaice". Marine Ecology Progress Series. 257: 247–257. doi:10.3354/meps257247. hdl:11250/109194. ISSN 0171-8630.
  16. ^ Mollet, Fm; Kraak, Sbm; Rijnsdorp, Ad (2007-12-06). "Fisheries-induced evolutionary changes in maturation reaction norms in North Sea sole Solea solea". Marine Ecology Progress Series. 351: 189–199. doi:10.3354/meps07138. ISSN 0171-8630.
  17. ^ Tobin, Declan; Wright, Peter J. (July 2011). "Temperature effects on female maturation in a temperate marine fish". Journal of Experimental Marine Biology and Ecology. 403 (1–2): 9–13. doi:10.1016/j.jembe.2011.03.018.
  18. ^ Mark A. Hixon, Darren W. Johnson, Susan M. Sogard, BOFFFFs: on the importance of conserving old-growth age structure in fishery populations, ICES Journal of Marine Science, Volume 71, Issue 8, October 2014, Pages 2171–2185, https://doi.org/10.1093/icesjms/fst200
 

This Pleuronectoidei-related article is a stub. You can help Wikipedia by expanding it.

Retrieved from "https://en.wikipedia.org/w/index.php?title=Pacific_sanddab&oldid=1258356264"