Spatial and Temporal Variability of Parasite Communities: Implications for Fish Stock Identification

The spatial and temporal variability of parasite communities have received little attention when used as biological tags for identifying fish stocks. This study evaluated the potential spatial and temporal variability of the parasite communities affecting three marine fish species collected between 1993 and 2017. To avoid the potential effect of host age in parasite communities, individuals of similar ages were selected: 1123 Engraulis ringens (12–24 months old), 1904 Trachurus murphyi (24–36 months old), and 630 Merluccius gayi (36–48 months old). Most taxa show differences in the prevalence at the spatial and temporal scales, but the prevalence of some larval endoparasites remains constant at the temporal scale. At the spatial scale, an analysis of similarity (ANOSIM) showed differences in the parasite communities of three species; a canonical analysis of principal coordinates (CAP) showed low values of correct allocations (CA; ≈50%) and values of allocation due to chance (AdC) were lower than the CA. At the temporal scale, an ANOSIM showed differences between the three species. A CAP showed low values of CA (≈50–60%) and the AdC was always lower than CA. Samples at the spatial scale were well allocated to their localities or nearby localities, suggesting a spatial stability. Samples from different years were not well discriminated, suggesting temporal variability. Therefore, in studies regarding parasites as a tool for stock identification, temporal variability must be taken into account.

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Mapping the origin of faunal assemblages using strontium isotopes

Paleobiology ◽

10.1017/s0094837300018066 ◽

2003 ◽

Vol 29 (2) ◽

pp. 197-204 ◽

Cited By ~ 14

Author(s):

Stephen Porder ◽

Adina Paytan ◽

Elizabeth A. Hadly

Keyword(s):

Spatial Scale ◽

Temporal Variability ◽

National Park ◽

Local Population ◽

Spatial And Temporal Variability ◽

Sr Isotopes ◽

Source Areas ◽

Population Responses ◽

Faunal Assemblages ◽

The Past

One of the greatest challenges in using faunal assemblages to make ecological or paleoecological interpretations is determining the spatial scale over which such analyses are applicable. As a result, it has been difficult to use these assemblages to test hypotheses about spatial and temporal variability in populations. Here we show that it is possible to use strontium (Sr) isotopes from bones and vegetation to statistically constrain the area sampled in two Holocene predator accumulations in northeastern Yellowstone National Park, Wyoming. Previous studies have used these sites to elucidate local population responses to climatic change, by assuming that the specimens originated within ~5 km of the site. We used Sr analyses to construct a likelihood curve that describes the probability that our samples were collected within a given radius of each site. Our results indicate that the specimens in both sites were derived from non-overlapping populations and that the collection radius has not changed detectably over the past 3000 years. This work underscores the promise of this technique for ascribing source areas to paleontological, biological, and ecological specimens.

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Interactions between fish and fisher's spatial distribution and behaviour: an empirical study of the anchovy (Engraulis ringens) fishery of Peru

ICES Journal of Marine Science ◽

10.1016/j.icesjms.2004.07.016 ◽

2004 ◽

Vol 61 (7) ◽

pp. 1127-1136 ◽

Cited By ~ 35

Author(s):

Sophie Bertrand ◽

Erich Díaz ◽

Miguel Ñiquen

Keyword(s):

Spatial Scale ◽

Spatial Dynamics ◽

Fishing Ground ◽

Fish Stock ◽

Commercial Fishing ◽

Spatial Concentration ◽

Time Period ◽

Engraulis Ringens ◽

Spatio Temporal ◽

Potential Interactions

Abstract Fishing data provide, with wide spatio-temporal coverage, inexpensive information about exploited species, but a precondition for their interpretation is a good comprehension of fish and fisher spatial dynamics and interactions. In Peru, anchovy (Engraulis ringens) is exploited by an industrial fleet of about 800 purse-seiners operating all along the coast. Using simultaneous acoustic survey and commercial fishing data for the 1998–2001 time period, we present a preliminary, exploratory, and empirical approach to identify the nature of potential interactions between Peruvian anchovy and fisher behaviour. We show that (i) Peruvian anchovy exhibited a composite spatial strategy for the study period, i.e. a change in biomass was associated with both change in geographical extension and density; (ii) fishing behaviour significantly varied within and among vessels in terms of travel duration, searching duration, and number of fishing sets; and (iii) interactions between fish and fisher behaviours differed according to the spatial scale. At a fish stock scale (the scale of fishing ground selection for fishers), fishing was more efficient with low biomass and high spatial concentration (low stock range and high biomass); at a local fish spatial scale (the scale of searching for a school inside the fishing ground), fishing performance was favoured by high mean local abundances and low spatial concentration (the way fish is distributed inside its stock range); finally, at the school scale (the scale of the fishing set), both high abundance and high spatial concentration were favourable to fishing success.

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Spatial and temporal variability of mobile macro-invertebrate assemblages associated to coralligenous habitat

Mediterranean Marine Science ◽

10.12681/mms.442 ◽

2014 ◽

Vol 15 (2) ◽

pp. 302 ◽

Cited By ~ 7

Author(s):

R. BEDINI ◽

L. BONECHI ◽

L. PIAZZI

Keyword(s):

Spatial Scale ◽

Temporal Variability ◽

Sampling Design ◽

High Variability ◽

Spatial And Temporal Variability ◽

Macroinvertebrate Assemblages ◽

Invertebrate Assemblages ◽

One Year ◽

Sessile Organisms

The study aimed to investigate patterns of spatial and temporal variability of mobile macroinvertebrate assemblages associated to coralligenous habitat. A multi-factorial sampling design was used to test the hypotheses that the structure of assemblages and their spatial and temporal variability changed in relation to substrate inclination. Moreover, macroalgae and sessile macro-invertebrates were also investigated in order to detect eventual relationship between sessile and mobile assemblages. A total of 236 mobile macro-invertebrate taxa were identified, among them 2 Platyhelminthes, 4 Sipuncula, 6 Nemertea, 27 Mollusca, 86 Annelida, 103 Arthropoda, 8 Echinodermata. Results of the study showed that mobile macro-invertebrate assemblages of coralligenous habitat were little influenced by the inclination of substrate and by the morphology of sessile organisms, as patterns of variation were different between the two assemblages. Mobile macro-invertebrate assemblages changed among sampling dates within one year period and they showed high variability at the spatial scale examined.

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