Search results for "fishery"

Intercohort competition causes spatial segregation in brown trout in artificial streams

1999

When together in a flume, 13-cm LS (age-1) trout appeared to increase their activity and behaved more aggressively, whereas 10-cm LS (age-0) trout tended to move less and were rarely aggressive in the presence of the larger size class. Both size classes were less mobile and preferred lower water velocities in winter than in summer, and increased their use of instream cover in winter. When both size classes were present, only small trout decreased their use of low water velocities and cover. The results indicate that intercohort competition may cause spatial segregation among size groups of brown trout, especially in winter when trout attempt to minimize their maintenance costs.

Effects of an invasive crayfish on the littoral macroinvertebrates of large boreal lakes are habitat specific

2013

Summary Invasive crayfish are widely acknowledged to have negative effects on benthic food webs in lakes, but few studies have investigated such effects at wider spatial scales and in varying habitats under natural conditions. We examined the effects of introduced signal crayfish (Pacifastacus leniusculus) on the macroinvertebrate assemblages of different habitats in two large boreal lakes. We evaluated whether the density, taxon richness and species composition are altered by the non-native crayfish and whether the responses are similar for stony and vegetated habitats and across a depth gradient. We also studied the influence of crayfish on periphyton biomass at stony sites, as a potentia…

The introduced signal crayfish and native noble crayfish have different effects on sublittoral macroinvertebrate assemblages in boreal lakes

2015

Draft Genome Sequences of Vibrio renopiscarius Strains CECT 8603T and CECT 8604, Two Marine Gammaproteobacteria Isolated from Cultured Gilthead Sea B…

2015

ABSTRACT Vibrio renopiscarius DCR 1-4-2 T (CECT 8603 T ) and DCR 1-4-12 (CECT 8604) were isolated from healthy gilthead sea bream ( Sparus aurata ) from Mediterranean fish farms (Castellón, Spain). Their draft genome sequences (30 and 44 contigs, respectively) have 4.3 Mbp and a G+C content of 45.2 mol% and contain almost 3,700 protein-encoding genes.

Otter Lutra lutra predation on farmed and free‐living salmonids in boreal freshwater habitats

2002

In this paper we aim to define whether fish farms or stocked trout streams substantially contribute to the diet of otters Lutra lutra living in freshwater habitats of Mid-Finland. Diet was assessed using spraint analysis. We especially focused on areas with fish farms and stocked trout Salmo trutta streams (salmonid-rich habitat) and used ‘normal’ (salmonid-poor) habitats as control. Frequency of salmonid remains in spraints was significantly higher in salmonid-rich habitats than elsewhere in all seasons, the difference increasing from summer to winter. In salmonid-rich habitats, however, salmonid consumption was not strongly seasonal. Data from spraint collection indicated a shift in activ…

Feeding ecology of the loggerhead turtle Caretta caretta in the western Mediterranean

2001

We studied the feeding ecology of juvenile loggerhead turtles Caretta caretta in the western Mediterranean based on the contents of the digestive tract of 54 turtles (range of CCL: 34–69 cm) seized in Barcelona (Spain) in 1991. Turtles had been captured in fishing trawls, but specific information about dates and localities is not available. Despite this limitation, we obtained interesting evidences about the foraging strategies of loggerheads, with potentially important conservation implications. We report 33 new taxa in the diet. Results indicated that western Mediterranean loggerheads feed in an opportunistic way. Numerically, fish made up the most important prey group, followed by pelagi…

Boat traffic in Lampedusa waters (Strait of Sicily, Mediterranean Sea) and its relation to the coastal distribution of common bottlenose dolphin (Tur…

2010

The volume of boat traffic and its potential connection to the coastal distribution of the common bottlenose dolphin (Tursiops truncatus) was evaluated off Lampedusa Island (Strait of Sicily). From July to September 2006 daily surveys were carried out at eight sites along the coast, three times a day, to assess the number, type, and size of boats moving, fishing, or stationed in Lampedusa waters. The study area was divided into four geographic areas: northwest, northeast, southwest, and southeast. Data were analyzed to determine the difference in the number of boats among the areas, sampling months, and times of day. The presence of dolphins was monitored by standardized land-based observat…

Purification and molecular characterization of the rhamnose binding lectin from sea bass (Dicentrarchus labrax) that agglutinate Gram positive and ne…

2013

Trend of Foreign Tourist Visits in the Conservation Area of the Cenderawasih Bay National Park (TNTC) with Special Interest on Whale Shark (Rhincodon…

2021

Tourist areas have a significant role in several aspects including economic, social and environmental. The national park has a considerable potential in the aspect of tourism. In addition to having mega biodiversity, the Cenderawasih Bay National Park (TNTC) also has a strong special attraction in term of whale shark, available year-round. Therefore, foreign tourism potential at TNTC is very high and much in demand by both local and foreign tourists. By processing visitation data, we were able to obtain trend and potentials in supporting the carrying capacity of whale shark tourism areas. Through these data, the estimated number of visitors in 2020 at TNTC was also obtained. Data were perfo…

Pesticide residues in some Baltic animals - a review of selected literature

1975

ABSTRACT During the last few years, considerable efforts have been devoted to the tracing of halogenated hydrocarbons, particularly DDT and PCB, and of mercury in Baltic animals. These investigations have already produced some important generalizations, which may be summarized as follows: (1) The concentrations of halogenated hydrocarbons and mercury in the tissues of Baltic animals are in general higher than those found in the corresponding species on the west coast of Sweden and in the Norwegian waters. (2) The highest levels of DDT compounds seem to occur in the animals of the southern Baltic and the Sound (oresund). (3) The highest contents of methylmercury in the Baltic fish occur in c…