Collaborative Studies: True Smelts
Along with the California Beach Fishermen's Association and H.T. Harvey and Associates, the Project received a small grant from Collaborative Fisheries Research West to study the night smelt population in Humboldt and Del Norte counties in 2014. Working with several commercial night smelt fishermen, we were able to obtain monthly regional fish samples across the entire north coast region in an effort to better understand aspects of night smelt life history. Additionally, we documented fish species commonly caught as bycatch while targeting night smelt in an effort to examine potential ecosystem impacts of the fishery.
Results from this one-year study were successful in improving our base of knowledge for night smelt. The population is clearly dominated by larger male fish; however, further research is needed to resolve several outstanding questions concerning the life history of this species. In observing commercial fishing activity, we documented relatively little bycatch in the fishery overall, and that the primary bycatch species were redtail surfperch (Amphistichus rhodoterus) and Pacific mole crab (Emerita analoga), the majority of which were released in live condition.
For detailed results from the collaborative smelt study, find the full technical report here:
Collaborative Research on the Spawning Population of Night Smelt (Spirinchus starksi) in Humboldt and Del Norte Counties, California (PDF)
April 15, 2015
Surf Fish Population Study
Surf fishes form the basis of a very popular recreational fishery in southern California. In 2008 an estimated 576,000 angler trips were made by nearshore anglers who caught surfperch, croakers, or California corbina, according to RecFIN data.
Despite the predominance of sandy beaches in the Southern California Bight (SCB), relatively little information exists on the surf zone fish community. In particular, spatial and temporal abundance information on surf fishes is lacking. The objectives of this study are to determine changes in surf fish abundances over time, among sites with differing exposure to wave action, and relative to tide heights and tidal movements. Results from this study will be compared to similar CDFW studies completed in the 1950s and 1990s.
Monthly beach seine sets at four sites (Bolsa Chica State Beach, Seal Beach, Belmont Shore, Hermosa Beach) within the SCB were conducted from May 2007 through September 2009. Beach seines are fishing nets with floats at the top and weights at the bottom to keep them open. Nets are set in about 10 feet of water and dragged to shore along the ocean bottom. Every fish caught in the net was identified, measured, and released. Sport fishes of interest (California corbina, spotfin croaker, yellowfin croaker, barred surfperch, and walleye surfperch) that were large enough to hold a t-bar tag and appeared to be in good condition were tagged prior to release. You may view pictures of these and other common surf zone fishes (PDF).
What to do if you catch a tagged fish
Each tag has a unique ID number and a CDFW phone number for anglers to call when they catch a tagged fish. Anglers are asked to provide the following information when reporting a tagged fish:
- tag number
- date caught
- general location or GPS coordinates
- total length (estimated or measured)
- any additional information
Flyers (PDF) have been posted at local bait shops and piers to inform anglers about the study. Results from this tagging study will help determine the seasonal and annual movement patterns of these fishes.
Findings to Date
As of September 2009, project staff have completed 386 hauls and caught 31,631 fish consisting of 47 species. The average number of fish per haul was around 82, but as many as 2,200 fish have been caught in a single haul.
List of fish species caught from May 2007 to September 2009
||Pacific chub mackerel
||barred sand bass
||California butterfly ray
||Pacific staghorn sculpin
||Albula sp. A
Abundance ranking of selected fishes caught by beach seine in three different CDFW studies/time periods.
- 3,270 fish have been tagged
- 18 fish have been recaptured
- 9 barred surfperch
- 3 California corbina
- 2 spotfin croaker
- 4 yellowfin croaker
- The greatest distance between tagging and recovery locations was the eight miles a large spotfin croaker traveled between the south end of Seal Beach and Huntington Beach pier.
Average CPUE by season for five popular sport fishes, May 2007 through September 2009.
Error bars denote one standard error.
Barred surfperch abundance remained relatively constant throughout all seasons, while spotfin croaker and California corbina abundances peaked in the summer and were lowest during the winter. Those seasonal differences may be due to inshore-offshore or upcoast-downcoast movements. Subsequent analyses suggest the dramatic increase in yellowfin croaker numbers in the spring was primarily due to increased numbers of young-of-the-year (YOY) in the catch. Increased walleye surfperch abundances in summer and fall were also due to an increase in abundance of YOY.
Tide height and flux for five popular sport fishes when CPUE was highest.
Fish illustrations provided by Dr. Larry Allen.
Although individuals of each species were caught throughout the tide cycle and at all tide heights, California corbina and spotfin croaker were more abundant during lower incoming tides, while barred surfperch, yellowfin croaker, and walleye surfperch were more abundant during slightly higher outgoing tides.
At Seal Beach, CA in November 2008 two Mexican lookdown, Selene brevoortii, juveniles were captured. The typical range for Mexican lookdown is from the southern tip of Baja California, Mexico to Panama, although adult specimens have been documented in south San Diego Bay during the 1997-98 El Niño event. This is the first documented occurrence of juvenile Mexican lookdown in California. The juvenile specimens represent an approximate 100 km northern range expansion from the Mexican lookdown's northernmost range boundary. Both specimens are now housed in the Los Angeles County Museum of Natural History fish collection (LACM 56886-1), and a scientific note has been published in the quarterly periodical California Fish and Game.
Two juvenile Mexican lookdown, Selene brevoortii, caught at Seal Beach on November 18, 2008.
(a) 63 mm standard length (SL); (b) 61 mm SL.