Methods for analysing fish stomach contents are listed and critically assessed
with a view to their suitability for determining dietary importance—this term is
defined. Difficulties in the application of these methods are discussed and,
where appropriate, alternative approaches proposed. Modifications which have
practical value are also considered. The necessity of linking measurements of
dietary ... hiện toàn bộ
A survey of the studies published in two leading fisheries journals revealed
that the analysis and measurement of condition, based on length‐weight data, has
been performed using a wide variety of indices and statistical procedures. Eight
forms of index were identified which can be categorized into those which measure
the condition of individual fish, i.e. condition factors‘, and those which
measu... hiện toàn bộ
FISH‐BOL, the Fish Barcode of Life campaign, is an international research
collaboration that is assembling a standardized reference DNA sequence library
for all fishes. Analysis is targeting a 648 base pair region of the
mitochondrial cytochromecoxidase I (COI) gene. More than 5000 species have
already been DNA barcoded, with an average of five specimens per species,
typically vouchers with author... hiện toàn bộ
Ongoing climate change is predicted to affect individual organisms during all
life stages, thereby affecting populations of a species, communities and the
functioning of ecosystems. These effects of climate change can be direct,
through changing water temperatures and associated phenologies, the lengths and
frequency of hypoxia events, through ongoing ocean acidification trends or
through shifts i... hiện toàn bộ
Felicity A. Huntingford, Colin E. Adams, Victoria A. Braithwaite, Sunil Kadri, T.G. Pottinger, Peter Sandøe, James Turnbull
Human beings may affect the welfare of fish through fisheries, aquaculture and a
number of other activities. There is no agreement on just how to weigh the
concern for welfare of fish against the human interests involved, but ethical
frameworks exist that suggest how this might be approached.Different definitions
of animal welfare focus on an animal's condition, on its subjective experience
of tha... hiện toàn bộ
From a total of 524 microsatellite loci considered in nearly 40 000 individuals
of 78 species, freshwater fish displayed levels of population genetic variation
(mean heterozygosity, h=0·46, and mean numbers of alleles per locus, a=7·5)
roughly similar to those of non‐piscine animals (h=0·58 and a=7·1). In contrast,
local population samples of marine fish displayed on average significantly
higher h... hiện toàn bộ
We present the first synthesis of the life history and ecology of seahorses,
compare relationships for seahorses with other marine teleosts and identify
research needs. Seahorses occurred primarily amidst temperate seagrasses and
tropical coral reefs. Population densities were generally low, ranging from 0 to
0·51 individuals m−2, but reached 10 m−2in some patches. Inferred life spans
ranged from ... hiện toàn bộ
Empirical relationships are presented to estimate in fishes, asymptotic length
(L∞) from maximum observed length (Lmax), length at first maturity (Lm) from L∞,
life span (tmax) from age at first maturity (tm), and length at maximum possible
yield per recruit (Lopt) from L∞ and from Lm, respectively. The age at Lopt is
found to be a good indicator of generation time in fishes. A spreadsheet
contain... hiện toàn bộ
Matthew S. Kornis, Norman Mercado‐Silva, M. Jake Vander Zanden
The round gobyNeogobius melanostomusis one of the most wide‐ranging invasive
fish on earth, with substantial introduced populations within the Laurentian
Great Lakes watershed, the Baltic Sea and several major European rivers. Rapid
expansion and deleterious ecosystem effects have motivated extensive research on
this species; here this research is synthesized. Maps of the global distribution
are p... hiện toàn bộ
The response of the brown trout to a single, short (c. 1 min) incidence of
handling stress was monitored for a period of 1 month post‐stress. Significant
changes were found in feeding behaviour, in the levels of plasma cortisol,
glucose and lactate, in the concentration of circulating lymphocytes and in the
degree of epidermal mucification. No changes were detected in the growth rate
and coefficie... hiện toàn bộ