Fish community size structure of small lakes: the role of lake size, biodiversity and disturbance

Abstract Greenstreet, S. P. R., Fraser, H. M., Rogers, S. I., Trenkel, V. M., Simpson, S. D., and Pinnegar, J. K. 2012. Redundancy in metrics describing the composition, structure, and functioning of the North Sea demersal fish community. – ICES Journal of Marine Science, 69: 8–22. Broader ecosystem management objectives for North Sea demersal fish currently focus on restoring community size structure. However, most policy drivers explicitly concentrate on restoring and conserving biodiversity, and it has not yet been established that simply restoring demersal fish size composition will be sufficient to reverse declines in biodiversity and ensure a generally healthy community. If different aspects of community composition, structure, and function vary independently, then to monitor all aspects of community general health will require application of a suite of metrics. This assumes low redundancy among the metrics used in any such suite and implies that addressing biodiversity issues specifically will require explicit management objectives for particular biodiversity metrics. This issue of metric redundancy is addressed, and 15 metrics covering five main attributes of community composition, structure, and function are applied to groundfish survey data. Factor analysis suggested a new interpretation of the metric information and indicated that a minimum suite of seven metrics was necessary to ensure that all changes in the general health of the North Sea demersal fish community were monitored properly. Covariance among size-based and species-diversity metrics was low, implying that restoration of community size structure would not necessarily reverse declines in species diversity.

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Climate change alters fish community size-structure, requiring adaptive policy targets

Fish and Fisheries ◽

10.1111/faf.12278 ◽

2018 ◽

Vol 19 (4) ◽

pp. 613-621 ◽

Cited By ~ 14

Author(s):

Ana M Queirós ◽

José Fernandes ◽

Lily Genevier ◽

Christopher P Lynam

Keyword(s):

Climate Change ◽

Fish Community ◽

Size Structure ◽

Community Size ◽

Adaptive Policy ◽

Policy Targets

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The role of habitat complexity in shaping the size structure of a temperate reef fish community

Marine Ecology Progress Series ◽

10.3354/meps11330 ◽

2015 ◽

Vol 532 ◽

pp. 197-211 ◽

Cited By ~ 18

Author(s):

R Trebilco ◽

NK Dulvy ◽

H Stewart ◽

AK Salomon

Keyword(s):

Reef Fish ◽

Habitat Complexity ◽

Fish Community ◽

Size Structure ◽

Temperate Reef ◽

Reef Fish Community ◽

Temperate Reef Fish

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Modelling recovery of Celtic Sea demersal fish community size-structure

Fisheries Research ◽

10.1016/j.fishres.2012.12.010 ◽

2013 ◽

Vol 140 ◽

pp. 91-95 ◽

Cited By ~ 13

Author(s):

Samuel Shephard ◽

Tak Fung ◽

Axel G. Rossberg ◽

Keith D. Farnsworth ◽

David G. Reid ◽

...

Keyword(s):

Fish Community ◽

Size Structure ◽

Demersal Fish ◽

Community Size ◽

Celtic Sea

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Fishing degrades size structure of coral reef fish communities

10.7287/peerj.preprints.2118 ◽

2016 ◽

Author(s):

James PW Robinson ◽

Ivor D Williams ◽

Andrew M Edwards ◽

Jana McPherson ◽

Lauren Yeager ◽

...

Keyword(s):

Coral Reef ◽

Reef Fish ◽

Fish Community ◽

Size Structure ◽

Fish Communities ◽

Fish Biomass ◽

Community Size ◽

Size Spectra ◽

Coral Reef Ecosystems ◽

Total Fish

Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra of coral reef fish communities at 38 US-affiliated Pacific islands, spanning from near pristine to highly human populated. Reef fish community size spectra slopes ‘steepened’ steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. In contrast, total fish community biomass was substantially lower on inhabited islands than uninhabited ones, regardless of human population density. Comparing the relationship between size spectra and reef fish biomass, we found that on populated islands size spectra steepened linearly with declining biomass, whereas on uninhabited islands size spectra and biomass were unrelated. Size spectra slopes also were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to biophysical conditions, being influenced by oceanic productivity, sea surface temperature, island type, and habitat complexity. Our results suggest that community size structure is more robust than total fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems.

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Variability in light absorption and scattering of phytoplankton in Patagonian waters: Role of community size structure and pigment composition

Journal of Geophysical Research Oceans ◽

10.1002/jgrc.20082 ◽

2013 ◽

Vol 118 (2) ◽

pp. 698-714 ◽

Cited By ~ 15

Author(s):

Amabile Ferreira ◽

Dariusz Stramski ◽

Carlos A. E. Garcia ◽

Virginia M. T. Garcia ◽

Áurea M. Ciotti ◽

...

Keyword(s):

Light Absorption ◽

Size Structure ◽

Pigment Composition ◽

Community Size

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Fishing degrades size structure of coral reef fish communities

10.7287/peerj.preprints.2118v1 ◽

2016 ◽

Author(s):

James PW Robinson ◽

Ivor D Williams ◽

Andrew M Edwards ◽

Jana McPherson ◽

Lauren Yeager ◽

...

Keyword(s):

Coral Reef ◽

Reef Fish ◽

Fish Community ◽

Size Structure ◽

Fish Communities ◽

Fish Biomass ◽

Community Size ◽

Size Spectra ◽

Coral Reef Ecosystems ◽

Total Fish

Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra of coral reef fish communities at 38 US-affiliated Pacific islands, spanning from near pristine to highly human populated. Reef fish community size spectra slopes ‘steepened’ steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. In contrast, total fish community biomass was substantially lower on inhabited islands than uninhabited ones, regardless of human population density. Comparing the relationship between size spectra and reef fish biomass, we found that on populated islands size spectra steepened linearly with declining biomass, whereas on uninhabited islands size spectra and biomass were unrelated. Size spectra slopes also were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to biophysical conditions, being influenced by oceanic productivity, sea surface temperature, island type, and habitat complexity. Our results suggest that community size structure is more robust than total fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems.

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Fishing and environment drive spatial heterogeneity in Celtic Sea fish community size structure

ICES Journal of Marine Science ◽

10.1093/icesjms/fsr137 ◽

2011 ◽

Vol 68 (10) ◽

pp. 2106-2113 ◽

Cited By ~ 11

Author(s):

Samuel Shephard ◽

Hans D. Gerritsen ◽

Michel J. Kaiser ◽

Holly S. Truszkowska ◽

David G. Reid

Keyword(s):

Spatial Heterogeneity ◽

Fish Community ◽

Size Structure ◽

Fishing Effort ◽

Trawl Survey ◽

Weak Effect ◽

Community Size ◽

Negative Effect ◽

Celtic Sea ◽

Sea Fish

Abstract Shephard, S., Gerritsen, H. D., Kaiser, M. J., Truszkowska, H. S., and Reid, D. G. 2011. Fishing and environment drive spatial heterogeneity in Celtic Sea fish community size structure. – ICES Journal of Marine Science, 68: 2106–2113. The Large Fish Indicator (LFI) is a univariate size-based indicator of fish community state that has been selected to support the OSPAR fish community Ecological Quality Objective (EcoQO). To operate this EcoQO, a survey-based LFI for each OSPAR region needs to be developed. However, fish communities in these regions are spatially heterogeneous, and there is evidence of within-region spatial variation in the LFI that could confound an overall indicator series. For Celtic Sea trawl-survey sites, spline correlograms indicate positive spatial autocorrelation at a similar range (∼40 km) for the LFI and for fishing effort (h year−1) from vessel monitoring systems. Statistical models reveal a strong negative effect on annual LFI by site of fishing effort within a radius of 40 km. There was a weak effect of fishing within 20 km and no effect at 10 km. LFI also varied significantly with substratum and with local fish community composition identified by a resemblance matrix derived from the survey data. Finally, there was a weak effect of survey year on LFI. Spatial stratification of LFI calculations may be necessary when developing size-based indicators for OSPAR or Marine Strategy Framework Directive regions.

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“No me des el pescado, enséñame a pescar” “Do not hand me fish, teach me how to fish” Community Lawyering in Puerto Rico: Promoting empowerment and self-help

International Journal of Clinical Legal Education ◽

10.19164/ijcle.v12i0.71 ◽

2014 ◽

Vol 12 ◽

pp. 83

Author(s):

Myrta Morales-Cruz

Keyword(s):

Community Development ◽

Fish Community ◽

Legal Aid ◽

Self Help ◽

Development Section ◽

The People ◽

The University ◽

Insight Into ◽

Special Meaning

<p>Law 232 of August 27, 2004 has a special meaning to the people residing in some of Puerto Rico's poorest communities. It was the result of the hard work, during a period of a year and a half, of leaders from some of these communities and my students, the students of the community development section of the Legal Aid Clinic of the University of Puerto Rico’s School of Law. The story of Law 232 can provide insight into what the role of a lawyer can be in the battle against poverty. To understand the story of this Puerto Rican law, one has to go back to August of 2002. During that month the University of Puerto Rico's School of Law Legal Aid Clinic inaugurated its community development section.</p>

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