Caulolatilus Princeps Research Articles

Feeding strategies of the ocean white fish (Caulolatilus princeps) and white spotted sand bass (Paralabrax albomaculatus) inside the Galapagos Marine Reserve

Understanding the diet of two demersal species, the ocean white fish (Caulolatilus princeps) and white spotted sand bass (Paralabrax albomaculatus) provides insights into the trophic strategies they have evolved to co-exist in rocky reefs and soft bottom habitats in the Galapagos Marine Reserve (GMR). We applied two complementary techniques (stomach content and stable isotopes analysis) to determine the trophic habits between species, and categories (sex, life stages and seasons). Sampling was carried out in several sites of fishing importance within the GMR between 2017 and 2018, obtaining 254 stomachs and 58 muscle samples for C. princeps, and 14 stomachs and 34 muscle samples for P. albomaculatus. Trophic spectrum (diet composition), of both predators contained pelagic and benthic prey. The slender anchovy (Anchoa ischana) was the most important prey for C. princeps with no significant differences in the diet between sex, life stages or seasons (p > 0.05); while the most important prey for P. albomaculatus was the threadfin bass (Pronotogrammus multifasciatus). The δ13C and δ15N signatures were significantly different among species (tvalue = 11.81, p < 0.05 and tvalue = 4.67, p <0.05, respectively) suggesting differences in the carbon source (i.e., feeding areas) as well as the preference for different trophic levels (i.e., different prey). Intraspecific analysis in C. princeps showed no differences within sex, life stage and seasons (p > 0.05). Feeding strategies were similar for both predators, with a reduced trophic niche and high variability between preys consumed. This work provides baseline information on two species of ecological and commercial importance within the GMR and highlights the value of trophic studies to generate useful information for an ecosystem-based fisheries management.

Metabarcoding Used for the First Time to Identify Prey of Wild Totoaba macdonaldi.

Totoaba macdonaldi is an endangered endemic fish of the Gulf of California. Overexploitation resulted in the Mexican government banning the fishing of this species in 1975, and it being listed as endangered. However, the species is still subject to illegal fishing. Despite its conservation status, little is known about totoaba biology. The present study aimed to implement, for the first time, a metabarcoding protocol to describe the totoaba diet. Four wild totoaba individuals, seized by Mexican law enforcement agents, were dissected, and their stomach contents were collected. Three representative amplicon libraries were generated for cephalopods, chordates, and eukaryotes. After sequencing, 18 different taxa were identified, of which 11 species were recognized as prey. The totoaba were found to have consumed Pacific anchovy (Cetengraulis mysticetus), flathead grey mullet (Mugil cephalus), bigeye croaker (Micropogonias megalops), northern anchovy (Engraulis mordax), ocean whitefish (Caulolatilus princeps), milkfish (Chanos chanos), and Pacific sardine (Sardinops sagax). Members of the Euphausiidae family (krill) were also identified. This study identified up to four times more species in much fewer samples than previous studies based on morphological recognition, thus confirming metabarcoding as an effective method for studying the feeding habits of this species and one providing the tools required for further analysis of the totoaba diet.

Mercury in fish tissues from the Galapagos marine reserve: Toxic risk and health implications

Fishing is one of the most important economic and cultural activities in Galapagos and Hg presence in aquatic ecosystems is a serious problem for human health, so its concentrations should be studied. We sampled five demersal species (Caulolatilus princeps, Caulolatilus affinis, Mycteroperca olfax, Hyporthodus mystacinus and Pontinus clemensi) and four pelagic species (Coryphaena hippurus, Acanthocybium solandri, Thunnus albacares and Seriolella violacea) to evaluate Hg concentration in muscle, liver and gonads. Hg was analyzed by Cold Vapor Atomic Absorption Spectrophotometry with Flow Injection System (CV-AAS-FIAS). Demersal species had higher Estimated Weekly Intakes (EWI) of Hg than pelagic species. According to the Codex Alimentarius (1995), EFSA (2018), FDA (2021) regulations, and according to the regulations in Europe, A. solandri, P. clemensi, and H. mystacinus were found above the maximum allowed concentration (MAC) (0.65, 0.65 and 1.26 mg/kg wet weight, respectively) so they could not be ingested nor commercialized. The Margin of Safety (MoS) of these species was above 1, so they could pose a risk to human health. We hypothesize that the Hg concentrations found in the studied species could come from the volcanism of the archipelago, since no major sources of anthropogenic Hg contamination can be found in the islands.

Metals in commercial fish in the Galapagos Marine Reserve: Contribution to food security and toxic risk assessment

Metal pollution in the marine environment can damage places with exceptional biodiversity such as the Galapagos Islands. For this reason, it is important to evaluate the toxic risk from metals derived from fish consumption and to perform a nutritional assessment. We sampled 20 individuals of demersal (Caulolatilus princeps and Mycteroperca olfax) and pelagic (Thunnus albacares and Seriolella violacea) species.The levels of the toxic elements (Al, B, Ba, Cd, Ni, Pb and Sr), and the macroelements, microelements and trace elements (Ca, Cr, Fe, K, Li, Mn, Mo, Mg, Na, V and Zn) of species muscle tissue were analyzed by Inductively Coupled Plasma Optical Spectrometry (ICP-OES).Demersal species have higher concentrations of Cr, K, Mg and Mo; while pelagic species have higher levels of Zn. M. olfax could potentially cause Cd toxicity so it is recommended not to ingest more than 86 and 73 g of this species (i.e. roughly, one serving) per week for men and women, respectively. None of the species could be marketed in Europe and the USA due to Cd level exceed the allowed limits by EFSA and FAO. Furthermore, the dietary intake of C. princeps is recommended due to its high concentration of Ca, Na, K, Mg and Cr, while T. albacares is recommended for people with Zn deficiency. However, due to the Cd level in C. princeps it is not recommended to ingest more than five servings per week. We attribute the source of metals in the studied fish from the volcanic origin of the islands rather than from human pollution. This is the first study that thoroughly estimate concentration of metals in commercial fish species and its contribution to food security in the Galapagos.

Early conservation benefits of a de facto marine protected area at San Clemente Island, California.

De facto marine protected areas (DFMPAs) are regions of the ocean where human activity is restricted for reasons other than conservation. Although DFMPAs are widespread globally, their potential role in the protection of marine habitats, species, and ecosystems has not been well studied. In 2012 and 2013, we conducted remotely operated vehicle (ROV) surveys of marine communities at a military DFMPA closed to all civilian access since 2010 and an adjacent fished reference site at San Clemente Island, the southernmost of California's Channel Islands. We used data extracted from ROV imagery to compare density and biomass of focal species, as well as biodiversity and community composition, between the two sites. Generalized linear modeling indicated that both density and biomass of California sheephead (Semicossyphus pulcher) were significantly higher inside the DFMPA. Biomass of ocean whitefish (Caulolatilus princeps) was also significantly higher inside the DFMPA. However, species richness and Shannon-Weaver diversity were not significantly higher inside the DFMPA, and overall fish community composition did not differ significantly between sites. Demonstrable differences between the DFMPA and fished site for two highly sought-after species hint at early potential benefits of protection, though the lack of differences in the broader community suggests that a longer trajectory of recovery may be required for other species. A more comprehensive understanding of the potential conservation benefits of DFMPAs is important in the context of marine spatial planning and global marine conservation objectives.

Spatial and Temporal Fishing Patterns at the Outer Banks of the Southern California Bight

We analyzed recreational and commercial catch records from 1980 to 2009 for the fishing blocks associated with the 5 southern offshore banks of the Southern California Bight (Cortes Bank, Tanner Bank, Northeast Bank, Cherry Ridge, and Garrett Ridge). Recreational fishers and divers targeted pelagic taxa (e.g., tunas and Yellowtail) but instead landed more benthic taxa (e.g., rockfishes, Ocean Whitefish, and California Sheephead). For the commercial fisheries, pelagics (Bluefin Tuna, Albacore, Skipjack, Yellowfin Tuna, Pacific Bonito, and Swordfish) were the most important taxa and represented a significant proportion (8%–27%) of the landings of these fishes in the bight. These fishes were caught primarily at Cortes and Tanner Banks, which together only represent 3.7% of the fishing grounds in the region. In addition, this proportion of catch of these critical species has been significantly increasing at the outer banks during this period. Based on their geography and physical oceanography, we propose that these offshore banks comprise a unique habitat for pelagic resources in the Southern California Bight.

Deep learning models for the prediction of small-scale fisheries catches: finfish fishery in the region of “Bahía Magadalena-Almejas”

Abstract Globally, over 80% of fisheries are at maximum sustainable levels or overexploited. However, small-scale fisheries (SSFs) in developing countries play a relevant role in coastal communities’ development with important impacts on the economy. The SSFs are normally multi-specific and due to the lack of data, studying them by simulation poses an important challenge especially forecasting models. These models are necessary to support management decisions or develop sustainable fisheries; therefore, models based on Deep Learning were proposed to forecast SSFs catch, using data from official catch landing reports (OCLRs), satellite images, and oceanographic data. The finfish fishery in Bahía Magdalena-Almejas (México) was used for the present study. According to an analysis of OCLRs, the target species of major importance in the fishery were identified and selected for the model. The proposed deep learning models used two artificial neural networks structures: non-linear autoregressive neural network and long-short term memory network, which were designed to assess and forecast monthly catch levels of Paralabrax nebulifer and Caulolatilus princeps. Models with a performance efficiency of R &amp;gt; 0.8, MSE &amp;lt; 300 were found, which indicate that the models are applicable in SSF with poor data and multi-specific fishery contexts, at low cost.

Small scale fisheries operative units in the west central region of the Gulf of California, Mexico

The multispecific and multigear character of small scale fisheries is complex and often difficult to understand, especially when basic data necessary for evaluation are scarce. In this study the distribution of spatial and temporal fishing pressure of operative fishery units OU was analysed. Each unit was integrated per vessel which, through similar forms of operation, takes advantage of the same species in the central region of the Gulf of California. The identification of the OU is based on a survey about the forms of operation and they were complemented with the catch data per species collected by the National Commission of Aquaculture and Fishing from 1998 to 2010. A hierarchical cluster analysis was applied and nine OUs were determined, which included: jig-caught jumbo squid; amberjacks with surface fishing nets; octopus with diving gear; groupers with hooks; shark with surface fishing nets; stingrays with bottom-set net; triggerfishes, mojarras, ocean whitefish and hogfish with hooks; weakfish, snappers, parrotfishes and grunts with bottom-set nets; Pacific sierra with surface fishing nets. The interaction processes between OUs are described through thematic maps in relation to the use of fishing areas and pressure by overlapping activities. It is proposed that when the fishermen have more than one fishing permit, they should choose what OU to work. Furthermore, if the permit is for finfish fishing they need to decide in what operative unit it is best to participate, accounting for factors such as abundance, price and distance to the fishing location. All of the OUs are relevant for the economy of the fishermen of the region and their interaction is necessary for maintaining fishery production.

Participatory management in a small-scale coastal fishery—Punta Abreojos, Pacific coast of Baja California Sur, Mexico

We describe the structure and historic landings of the Punta Abreojos fishing cooperative (Baja California Sur, Mexico) for the period between 2001 and 2015 to understand the dynamics of an economically and ecologically successful coastal fishing community according to catches and the direct income of fishers. A total of 21 commercial species were classified into three major groups: cultural resources, target resources and complementary resources. The most important resource in terms of total biomass was Paralabrax nebulifer (58.4%), followed by Panulirus interruptus and P. inflatus (13.6%). Seriola lalandi, Atractoscion nobilis, Caulolatilus princeps, Paralichtys californicus and P. woolmani made up minor proportions of the total biomass contributing 7.0%, 5.7%, 3.4% and 3.2% respectively. Haliotis fulgens and H. corrugata represented just 1.1% of the total biomass caught. Lobsters were the most profitable source of direct income for fisherman (77.5%), followed by the green and pink abalone (10.4%), barred sand bass (5.6%), white seabass (2.7%), California and speckled flounder (1.2%), yellowtail (1%) and whitefish (0.4%). The rest of the catch was composed of six species of finfish that represented 4.1% of the total catch biomass and 0.4% of the revenues from fishing.This work provides a first clear base-line description of the fisheries in Punta Abreojos which implements a management program that aims to ensure the wellbeing of the fishers and the fishery. The cooperative has been successful in maintaining catch at levels considered optimal to sustain revenues and continued annual landings. A management and cooperative structure that allows for adaptive change whilst maintaining revenues of the fishers is testament to the stewardship of the community and the participatory management upon which the community is built. For this reason, Punta Abreojos should be considered an example of a successful small-scale fishing cooperative that other, less successful fishing groups, can learn from.

Eumetazoan parasites of two marine fish species from Baja California, Mexico:Sebastes miniatus(Jordan &amp; Gilbert, 1880) andCaulolatilus princeps(Jenyns, 1840)

It is hypothesized that two fish species sharing a same demersal habitat might show a similar community of parasites. The aim of this study was to compare the parasite community component of of two marine fishes on the northwest coast of México of economical interest, the vermilion rockfish Sebastes miniatus and the ocean whitefish Caulolatilus princeps. From February to December 2005, 210 specimens of S. miniatus (85–550 mm total length TL) and 91 C. princeps (85–550 mm TL) were obtained from the San Quintín sportfishing catch, at Pacific Baja California. Skin, eyes, fins and gill cavity were examined in situ, and their internal organs removed for later analysis, including a portion of flesh. In S. miniatus, 12 parasite taxa were identified as belonging to Monogenea, Digenea, Cestoda, Nematoda, Acanthocephala and Copepoda; the stomach, pyloric caeca, and intestine (digestive tract) were the most parasitized organs with seven of the 12 species. In S. miniatus, the most abundant parasite was Parabothriocephalus sagitticeps (80.8 individuals/host ± 33.4 SE: standard error), highest prevalence was Microcotyle sebastis (92.6%), and the highest average intensity of infection was the cestode P. sagitticeps (190.4 ± 48.1 SE). The C. princeps showed six species belonging to Monogenea, Digenea, Nematoda and Copepoda; the digestive tract presented the greatest infestation, with four of the six species recorded. The most abundant nematode was Hysterothylacium aduncum (16.5 ± 3.5 individuals/host), the main prevalent species was Anisakis sp., and the highest value of infection intensity was by Hatschekia sp. The nematodes Anisakis sp. and H. aduncum were shared between the two host fishes, and are a zoonotic risk to humans if the fishes are not cooked properly.

Anisakinae Nematodes in Two Commercial Marine Fish from the East Pacific of Baja California, Mexico

Abstract: This study documents temporal changes in abundance and prevalence of larval anisakid nematodes in two commercially important fish; the vermilion rockfish Sebastes miniatus, and the ocean whitefish Caulolatilus princeps, collected in coastal waters of San Quintin, Baja California, Mexico. Anisakis sp., Hysterothylacium aduncum, and Pseudoterranova decipiens (Anisakidae) were found in S. miniatus, while H. aduncum and P. decipiens were present in C. princeps. The vermilion rockfish constitutes a new host for H. aduncum; C. princeps is a new host for Anisakis sp. and H. aduncum. San Quintin constitutes a new geographic locality for Anisakis sp. and H. aduncum. Hysterothylacium aduncum was the most abundant parasite (S. miniatus = 37; C. princeps = 15.5), and Anisakis sp. was the most prevalent species (S. miniatus = 91.8%; C. princeps = 95%). The nematode abundance increased in summer in both S. miniatus and C. princeps. Both species were highly infected with nematode larval stages of Anisakis sp.,...

Parasite structure of the Ocean Whitefish Caulolatilus princeps from Baja California, México (East Pacific)

The metazoan parasite fauna of Caulolatilus princeps from northern Baja California, Mexico is quantitatively described for the first time. Further, the ecological aspects of prevalence, abundance, and intensity of infection are examined through an annual cycle. Six parasite species were recorded; 2 ectoparasites (1 monogenean and 1 copepod) and 4 endoparasites (2 digeneans and 2 nematodes). The digeneans Choanodera caulolatili and Bianium plicitum, the nematodes Anisakis sp. and Hysterothylacium sp., and the copepod Hatschekia sp. set new geographical and host records. The highest values of prevalence and abundance were in Anisakis sp. (prevalence = 93.3%, abundance = 12.4 ± 4.7 ind/host) and in Hysterothylacium sp. (prevalence = 86.6%, abundance = 16.5 ± 3.4 ind/host). The mean intensity of infection showed maximum values in summer (August = 14.2) and minimums in winter (February = 4.2). The mean intensity was higher in Hatschekia sp. (20.3 ± 7.8) followed by Hysterothylacium sp. (18.6 ± 1.4) and Anisakis sp. (12.9 ± 2.2). Larval stages of Anisakis and Hysterothylacium were particularly important due to their high abundance and prevalence, because they represent a human health risk (anisakiasis). In addition, the relationships between the metazoan parasites of C. princeps and host size and weight, fish condition and water temperature (bottom) are discussed.

Essential (Cu) and nonessential (Cd and Pb) metals in ichthyofauna from the coasts of Sinaloa state (SE Gulf of California)

With the aim of giving an overview on concentration and distribution of Cd, Cu, and Pb in fish from the coasts of Sinaloa state (SE Gulf of California), specimens with different feeding habits were collected in five locations. Sampling occurred between June 2003 and March 2004. Metal analyses on fish tissues were made by graphite furnace (Cd, Pb) and flame (Cu) atomic absorption spectrophotometry. Metal concentrations in tissues of carnivorous fish were grouped together and compared with corresponding concentrations in non-carnivorous fish; Cu and Pb levels were significantly (p < 0.05) higher in liver of non-carnivorous species. Though no samples exceeded the maximum level set in international legislation for fish, from the perspective of the public health and considering the legal limits of fishery products for human consumption, Cu concentrations were exceeded (in tissues different from muscle) in four carnivorous and five non-carnivorous species according to the Australian legislation. In the case of Cd, two carnivorous species (Pomadasys leuciscus and Caulolatilus princeps) and one non-carnivorous species (Mugil cephalus), showed concentrations over the maximum level of 2 microg g(-1) dry weight considered in the Mexican legislation. Considering average amounts of fish consumption in Mexico, daily mineral intake (DMI) values for Cu and percentage weekly intake (PWI) of Cd and Pb were estimated; none of the analyzed metals in edible portion of analyzed fish could be detrimental to humans.

Fine-scale movement patterns, site fidelity, and habitat selection of ocean whitefish ( Caulolatilus princeps)

The fishery for California groundfishes is managed using broad species complexes, although some non-groundfish species are managed similarly due to the perception of shared behavioral characteristics. This study integrates acoustic telemetry and a GIS to quantify movement patterns of one such species, the ocean whitefish ( Caulolatilus princeps) in a marine protected area. Seventeen ocean whitefish were tagged and actively tracked over multiple 24-h periods to measure fine-scale movement patterns. Home ranges based on 95% kernel utilization distributions averaged 20,439 ± 28,492 (±S.D.) m 2. Fish were active during the day, foraging over sand habitat at depths averaging 21 ± 8 m, but were inactive at night, taking refuge near rocky reefs at depths averaging 15 ± 7 m. Seventeen additional fish were tagged with coded acoustic transmitters and passively tracked using automated underwater acoustic receivers for up to 1 year. Approximately 75% of these fish exhibited long-term (1 year) fidelity to home ranges in the study area. Results suggest that MPAs can be an effective means of protecting populations of ocean whitefish and based on their habitat associations, ocean whitefish can be managed separately from other reef associated groundfishes.

Estructura de tallas, selectividad y composición específica de las capturas en trampas para peces marinos en el Golfo de California

We analyzed the performance of three traps for marine fish between October 2005 and August 2006 in the Gulf of California, Mexico. The performance was measured as difference in selectivity, fish diversity, size structure and yield. The samples were collected with quadrangular traps 90 cm wide, 120 cm long and 50 cm high. Trap type 1 had a 5 x 5 cm mesh (type 2: 5 x 5 cm including a rear panel of 5 x 10 cm; trap 3: 5 x 10 cm). Most abundant in our traps were: Goldspotted sand bass (Paralabrax auroguttatus), Ocean whitefish (Caulolatilus princeps), Spotted sand bass (P. maculatofaciatus) and Bighead tilefish (C. affinis); there was no bycatch. The number offish per trap per haul decreased when mesh size was increased. We also observed a direct relationship between mesh size and average fish length. By comparing our traps with the authorized fishing gear (hooks-and-line) we found that the size structure is larger in traps. Traps with larger mesh size were more selective. Consequently, we recommend adding traps to hooks-and-line as authorized fishing gear in the small scale fisheries of the Sonora coast, Mexico.

Gonadal development and spawning of female ocean whitefish, Caulolatilus princeps (Pisces: Branchiostegidae) in the Bay of La Paz, B.C.S., Mexico

The developmental stages of the gonads and the spawning season of the ocean whitefish, Caulolatilus princeps, were determined. Gonad maturation is annual, and the spawning season is prolonged, from late autumn to early spring. From November to March, around 80% of the females were in an advanced mode of gonadal development, and in April most gonads were spent. From May to October the gonads were at rest and preparing for the next spawning season.The gonadosomatic index describes the reproductive activity of the species adequately.

Gonadal development and spawning of female ocean whitefish, Caulolatilus princeps (Pisces: Branchiostegidae) in the Bay of La Paz, B.C.S., Mexico

Gonadal development and spawning of female ocean whitefish, Caulolatilus princeps (Pisces: Branchiostegidae) in the Bay of La Paz, B.C.S., Mexico

Feeding habits of the ocean whitefish, Caulolatilus princeps Jenyns 1842 (Pisces: Branchiostegidae), in La Paz Bay, B.C.S., Mexico

A total of 198 digestive tracts of ocean whitefish (Caulolatilus princeps, Jenyns, 1842) were examined from monthly catches, from February 1986 to January 1987. Using four indices (numeric, volumetric, frequency of occurrence and relative importance), the food components of the trophic spectrum were determined and categorized. This was made up of five major taxa: annelids, molluscs, crustaceans, echinoderms and fishes. The spectrum is dominated, most of the year, by the ostracod Conchoecia pacifìca, along with other secondary food items like hyperiid amphipods (Vibilia sp.), euphausiids (Nycthiphanes simplex), galatheids (Pleuroncodes planipes), pteropod molluscs (Hyaloselix striata, Clio piramidata), cephalopods (Loligo opalescens) and fishes, and with a range of incidental food items, like gammarids (Ampheliscidae), crab larvae (Callinectes sp.), isopods, penaeids, thalassinoideans, small gastropods, polychaetes and echinoderms. There are no significant differences in the spectra from males and females (Wilcoxon’s test, P = 0.05). The number of food components in the diet seems to increase with length. The most intensive feeding takes place between the end of the reproductive period and its start. In conclusion, the ocean whitefish is a passive predatory teleost, that feeds mainly during daylight hours upon organisms associated with the sea floor.

Resonance Structure in Echoes from Schooled Pelagic Fish

Explosive acoustic sources were used to obtain echoes from aggregations and schools of commercially important marine fish. Narrow-band spectral analysis of the echoes from these targets revealed significant structure in the frequency range from 200 Hz to 5 kHz. The targets were partially captured after the acoustic tests; three yielded northern anchovy (Engraulis mordax), one consisted of a mix of anchovy and jack mackerel (Trachurus symmetricus), and the last sample contained an aggregation of seven species of rockfish (Sebastes), whitefish (Caulolatilus princeps), and a striped seaperch (Embiotoca lateralis). The results of the direct biological sampling were combined with theoretical predictions for the resonant swimbladder response and compared with the experimentally observed resonances.

Resonant Structure in Echoes from Schooled Marine Fish

Explosive acoustic sources have been used to ensonify aggregations and schools of commercially important marine fish. Narrow-band spectral analysis of the echoes from these targets reveals significant structure in the frequency range 200 Hz–5 kHz. The targets were sampled biologically, three yielding northern anchovy (Engraulis mordax), one consisting of a mix of anchovy and jack mackerel (Trachurus symmetricus), and the last sample containing an aggregation of seven species of rockfish (Sebastes), whitefish (Caulolatilus princeps}, and striped perch (Embiotica lateralis). The results of the direct biological sampling are combined with theoretical predictions for the resonant swimbladder response and are compared with the experimentally observed resonances.