The Influence of Environmental Factors and Fishing Pressure on Catch Rates of Diplodus vulgaris

In passive fisheries, such as angling, the fishing success depends on the ultimate decision of a fish to ingest the bait, based on an individual’s internal state, previous experience, and threat perception. Fish surviving capture by anglers are known to be less vulnerable, and catch rates usually quickly decline with increasing fishing effort. Previous theoretical models have thus suggested fishing closures as a means to recover responsiveness of fish to angling gear and maintain catch rates, yet empirical support remains limited. In a controlled replicated pond experiment, we evaluated the effects of temporal variation in fishing pressure on catch rates of rainbow trout (Oncorhynchus mykiss) by simulating short-term fishing closures. Fishing closures increased catch rates and population-level catchability by reducing threat perception at the population level and allowing released individuals to return to a vulnerable state. Our experimental results show that periodic fishing closures benefit catch rates but at the risk of aggravating the likelihood of overharvesting.

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The effects of environmental factors and fisheries management on recreational catches of perch Perca fluviatilis in the Czech Republic

Aquatic Living Resources ◽

10.1051/alr/2019013 ◽

2019 ◽

Vol 32 ◽

pp. 15 ◽

Cited By ~ 4

Author(s):

Roman Lyach ◽

Jiri Remr

Keyword(s):

Environmental Factors ◽

Central Europe ◽

Fisheries Management ◽

Perca Fluviatilis ◽

Fishing Pressure ◽

Recreational Fisheries ◽

The Czech Republic ◽

Perch Perca Fluviatilis ◽

Average Body ◽

Average Body Weight

The Eurasian perch Perca fluviatilis is an important fish species in both commercial and recreational fisheries. However, there is concern that perch populations in Central Europe are decreasing. This study aimed to assess the effects of environmental factors and management on recreational perch catches. Data from individual angling logbooks collected by the Czech Fishing Union on 229 fishing grounds during the period 2005–2016 were used in this study. In total, almost 60 000 perch weighing 17 500 kg were recorded. During the study period, total perch catches decreased by 60%, catch per fishing visit decreased by 70%, average body weight of caught perch increased by 18%, and percentage of fishing grounds with perch catches decreased by 13%. The results indicated that the decreasing catches were due to increasing fishing pressure. Further, fishing grounds with higher fishing visit rates had higher catches in general but lower catch per fishing visit. Larger and more productive rivers also showed higher catches. In contrast, the intensity of fish stocking did not affect catches. In conclusion, perch populations in Central Europe are likely under high fishing pressure, and the pressure is further increasing.

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The Influence of Environmental Factors and Mitigation Measures on By-Catch Rates of Seabirds by Japanese Longline Fishing Vessels in the Australian Region

Emu - Austral Ornithology ◽

10.1071/mu98042 ◽

1998 ◽

Vol 98 (4) ◽

pp. 305-316 ◽

Cited By ~ 45

Author(s):

Neil Klaer ◽

Tom Polacheck

Keyword(s):

Environmental Factors ◽

Mitigation Measures ◽

Australian Region ◽

Fishing Vessels ◽

By Catch ◽

Catch Rates

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Angler and environmental influences on walleye Sander vitreus and muskellunge Esox masquinongy angler catch in Escanaba Lake, Wisconsin 2003–2015

PLoS ONE ◽

10.1371/journal.pone.0257882 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257882

Author(s):

Stephanie L. Shaw ◽

Kathryn M. Renik ◽

Greg G. Sass

Keyword(s):

Environmental Factors ◽

Solar Radiation ◽

Open Water ◽

Weather Conditions ◽

Catch Rate ◽

Sander Vitreus ◽

Memory Retention ◽

Esox Masquinongy ◽

Catch Rates ◽

Diel Period

Angler trip success and catch rates are dependent upon a fishes’ vulnerability to angling. Angling vulnerability can be influenced by angler-specific attributes (i.e., bait choice, lure size, use of a guide), and individual fish traits (i.e., boldness, aggression, stress responsiveness, and memory retention). The mechanisms that function in a fishes’ angling vulnerability, and contribute to catch rate, are likely correlated with environmental factors however, the influence of environmental factors on angling vulnerability are not well understood. We used the long-term (1946 –present) compulsory creel dataset from Escanaba Lake, WI, USA to test for interactions between angling vulnerability (i.e., angler trip success and catch rates) and environmental factors to better understand these dynamics in recreational fisheries. Our objective was to test for the influence of angler associated variables and environmental factors on open water angler trip success (i.e., catch ≥ one fish) and catch rate of walleye Sander vitreus and muskellunge Esox masquinongy during 2003–2015 using a hurdle model approach. Fishing trip success and catch rates for both species were most strongly influenced by angler-related variables (i.e., guide status, bait type, the proportion of the fish population previously caught). Environmental factors associated with lower light intensity (i.e., diel period, mean daily solar radiation, solar-Julian day interaction) had a positive influence on walleye vulnerability. Lower air temperatures and lunar position (moon overhead or underfoot) and phase (gibbous’ and full moon) also had a positive effect on walleye angling. Muskellunge trip success and catch rate were positively influenced by light metrics (i.e., diel period and mean daily solar radiation) and increased with air temperature. Lunar variables (position and phase), as well as wind speed and direction also influenced muskellunge angling vulnerability. A better understanding of the influence of environmental factors on angling vulnerability is an important component of fisheries management as management goals focus on balancing fish populations and creating satisfactory catch rates to enhance the angling experience. Our results suggest that angler-specific variables, light, temperature, lunar, and weather conditions influenced species-specific angling vulnerability for walleye and muskellunge.

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Hudson River Fishes and their Environment

Hudson River Fishes and their Environment ◽

10.47886/9781888569827.ch17 ◽

2006 ◽

Keyword(s):

Blue Crab ◽

Striped Bass ◽

White Perch ◽

River Estuary ◽

Hudson River ◽

Fishing Pressure ◽

Survey Period ◽

River Herring ◽

Unit Effort ◽

Catch Rates

Abstract.—Recreational fishing throughout the Hudson River estuary from the federal dam at Troy (river kilometer [rkm] 243) to the George Washington Bridge (rkm 19) was investigated during March 2001 through March 2002. Aerial counting surveys and angler interviews at nearly 200 access points were used to estimate fishing pressure, catch and harvest, catch rates, and various angler attributes. Fishing pressure for the mid-March through November period was estimated at 446,621 angler-hours. Most effort occurred in the late spring by anglers north of the Bear Mountain Bridge (rkm 74). Angling from boats comprised 72.6% of total effort. The total number of fish caught and harvested was estimated at 212,426 and 44,479 individuals, respectively, representing 31 species plus blue crab Callinectes sapidus. Most of the total catch was by boat anglers, although over the entire survey period shore anglers harvested the most fish. In sequence, striped bass Morone saxatilis, river herring Alosa spp., and white perch M. americana were the three most abundant species caught, whereas river herring, white perch, blue crab, and striped bass formed most of the harvest. Catch per unit effort (CPUE) and harvest per unit effort (HPUE) of shore anglers (0.69 fish/h and 0.22 fish/h) were higher than that of boat anglers (0.44 fish/h and 0.02 fish/h). Most anglers throughout spring sought striped bass, whereas during summer and fall boat anglers sought primarily black bass Micropterus spp., with much effort occurring during tournaments. Shore anglers were less focused and sought a broader variety of species. As a group, anglers fishing south of the Bear Mountain Bridge were less aware of fish consumption advisories due to contaminants than anglers fishing elsewhere in the estuary.

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Association of Environmental Factors in the Taiwan Strait with Distributions and Habitat Characteristics of Three Swimming Crabs

Remote Sensing ◽

10.3390/rs12142231 ◽

2020 ◽

Vol 12 (14) ◽

pp. 2231 ◽

Cited By ~ 1

Author(s):

Muhamad Naimullah ◽

Kuo-Wei Lan ◽

Cheng-Hsin Liao ◽

Po-Yuan Hsiao ◽

Yen-Rong Liang ◽

...

Keyword(s):

Environmental Factors ◽

Taiwan Strait ◽

Swimming Crab ◽

Crab Species ◽

Chl A ◽

Catch Rates ◽

The Taiwan Strait ◽

Autumn And Winter ◽

High Catch ◽

Swimming Crabs

Information regarding the oceanic environment is crucial for determining species distributions and their habitat preferences. However, in studies on crustaceans, especially swimming crabs, such information remains poorly utilized, and its effects on crab communities in the Taiwan Strait (TS) has not been well documented. The purpose of this study was to understand the relationship between the catch rates of three swimming crab species and environmental factors in the TS. We fitted generalized additive models (GAMs) to logbooks and voyage data recorder data from Taiwanese crab vessels (2011–2015), developed a species distribution model, and predicted catch rates for these three swimming crab species based on the GAM output. The chlorophyll-a (Chl-a) concentration was related to the high catch rates of Chrybdis feriatus and Portunus sanguinolentus, whereas bottom temperature (BT) was related to high catch rates of Portunus pelagicus. The variance percentages for each crab species indicated that high catch rates of C. feriatus and P. sanguinolentus occurred in a Chl-a concentration > 0.5 mg/m3, whereas P. pelagicus catch rates exhibited negative correlations with BTs > 25 °C. The model predicted high catch rates of C. feriatus in the north of the TS during autumn and winter, whereas P. pelagicus was observed to the south during summer and autumn. P. sanguinolentus was predicted to be widely distributed around the TS and distributed further to the northern area during autumn and winter. These findings revealed that each species responds to spatiotemporal environmental variations. Understanding the distributions and habitats of these three crabs is vital in fisheries resource management and conservation planning.

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Effects of environmental factors on the spatio-temporal distribution of striped marlin catch rates off Cabo San Lucas, Baja California Sur, Mexico

Fisheries Research ◽

10.1016/j.fishres.2014.09.007 ◽

2015 ◽

Vol 166 ◽

pp. 47-58 ◽

Cited By ~ 9

Author(s):

Sofía Ortega-García ◽

Edgardo Camacho-Bareño ◽

Raúl O. Martínez-Rincón

Keyword(s):

Environmental Factors ◽

Baja California ◽

Temporal Distribution ◽

Baja California Sur ◽

Spatio Temporal ◽

Catch Rates

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Steam trawl catches from south-eastern Australia from 1918 to 1957: trends in catch rates and species composition

Marine and Freshwater Research ◽

10.1071/mf00101 ◽

2001 ◽

Vol 52 (4) ◽

pp. 399 ◽

Cited By ~ 17

Author(s):

N. L. Klaer

Keyword(s):

World War Ii ◽

Early Years ◽

Catch Rate ◽

Fishing Pressure ◽

Eastern Australia ◽

Commercial Species ◽

History Of ◽

Catch Rates ◽

Pressure Changes ◽

Increased Retention

Haul-by-haul steam trawler catch and effort data for 1918–23, 1937–43 and 1952–57, which cover a large portion of the history of steam trawling in the Australian South East Fishery, were examined in detail for the first time. There were 64371 haul records in total. The catch-rate for all retained catch combined shows a strong decline overall, with a brief recovery during World War II, probably due to increased retention of previously discarded species. The fishing fleet moved to more distant fishing grounds and deeper waters as the catch-rate declined. The catch-rates of the main commercial species followed a similar pattern in a number of regions within the fishery. The catch-rate of the primary target species – tiger flathead (Neoplatycephalus richardsoni) – dropped considerably from the early, very high, catch-rates. Chinaman leatherjacket (Nelusetta ayraudi) and latchet (Pterygotrigla polyommata) – species that were apparently abundant in the early years of the fishery, virtually disappeared from catches in later years. The appearance of greater catches of jackass morwong (Nemadactylus macropterus), redfish (Centroberyx affinis) and shark/skate during the war and afterwards was probably due to increased retention of catches of these species. The disappearance of certain species from the catch may be due to high fishing pressure alone, or to a combination of fishing pressure, changes in the shelf habitat possibly caused by the trawl gear, and environmental fluctuations.

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