An Indigenous Model of a Contested Pacific Herring Fishery in Sitka, Alaska

2015 ◽  
Vol 6 (1) ◽  
pp. 94-117 ◽  
Author(s):  
Thomas F. Thornton ◽  
Harvey Kitka
Keyword(s):  
Marine Ecosystem ◽  
Single Species ◽  
Spatiotemporal Analysis ◽  
Ecological Knowledge ◽  
Pacific Herring ◽  
Clupea Pallasi ◽  
Closed Area ◽  
Key Species ◽  
The Status ◽  
Relative Potential

This paper uses GIS and spatiotemporal analysis of a historically and culturally modified marine ecosystem to evaluate Pacific herring abundance, declines, vulnerabilities, and future prospects, about which a Native Tribe and state fisheries managers disagree. In 2008, the Sitka Tribe of Alaska (STA) requested that an area within its traditional waters be closed to commercial sac roe fishing to protect spawning Pacific herring (Clupea pallasi), a key species for Native subsistence and marine ecosystem health. This proposal was opposed by the Alaska Department of Fish and Game (ADF&G), which estimated that adequate biomass was available to accommodate all herring users' needs. The disagreement exposes divisions between the Tribe's and the State's conceptualizations of the status, health, and management priorities for fisheries and marine ecosystems. The Tribe's model is one of cultivated abundance, wherein herring eggs are harvested conservatively and habitat is enhanced to make coastal spawning areas more productive, stable, and resilient. The State's paradigm, in contrast, follows a constitutional mandate to manage fisheries for Maximum Sustained Yield (MSY). A single-species biomass model is used to estimate a “surplus” herring for commercial roe harvesting within management areas. This work analyses and compares the spatiotemporal prescriptions of State and Indigenous models of herring fisheries management as they are used within debates over a closed area (Proposal 239), and assesses their relative potential for improving herring fisheries and marine ecosystem management using a combination of GIS spatial and scientific analysis and traditional ecological knowledge.

scholarly journals Camera Trapping to Assess Status and Composition of Mammal Communities in a Biodiversity Hotspot in Myanmar

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 880
Author(s):  
Giacomo Cremonesi ◽  
Francesco Bisi ◽  
Lorenzo Gaffi ◽  
Thet Zaw ◽  
Hla Naing ◽  
...  
Keyword(s):  
Human Disturbance ◽  
Habitat Degradation ◽  
Single Species ◽  
Wildlife Trade ◽  
Ecosystem Functions ◽  
Occupancy Models ◽  
Apex Predators ◽  
Disturbed Area ◽  
The Status ◽  
Mammal Communities

Tropical forests comprise a critically impacted habitat, and it is known that altered forests host a lower diversity of mammal communities. In this study, we investigated the mammal communities of two areas in Myanmar with similar environmental conditions but with great differences in habitat degradation and human disturbance. The main goal was to understand the status and composition of these communities in an understudied area like Myanmar at a broad scale. Using camera trap data from a three-year-long campaign and hierarchical occupancy models with a Bayesian formulation, we evaluated the biodiversity level (species richness) and different ecosystem functions (diet and body mass), as well as the occupancy values of single species as a proxy for population density. We found a lower mammal diversity in the disturbed area, with a significantly lower number of carnivores and herbivores species. Interestingly, the area did not show alteration in its functional composition. Almost all the specific roles in the community were present except for apex predators, thus suggesting that the effects of human disturbance are mainly effecting the communities highest levels. Furthermore, two species showed significantly lower occupancies in the disturbed area during all the monitoring campaigns: one with a strong pressure for bushmeat consumption and a vulnerable carnivore threatened by illegal wildlife trade.

Diet mixing in an aquatic carnivore, the harbour seal

2005 ◽  
Vol 83 (6) ◽  
pp. 851-859 ◽  
Author(s):  
Stephen J Trumble ◽  
Michael A Castellini
Keyword(s):  
Dry Matter ◽  
Single Species ◽  
Pacific Herring ◽  
Mixed Diet ◽  
Feeding Frequency ◽  
Digestible Energy ◽  
Diet Mixing ◽  
Walleye Pollock Theragra Chalcogramma ◽  
Harbour Seals ◽  
The Mean

To determine the effects of diet mixing on digestive performance, harbour seals (Phoca vitulina L., 1758) were offered either pure diets of Pacific herring (Clupea pallasii Valenciennes, 1847) or walleye pollock (Theragra chalcogramma (Pallas, 1814)) or a 1:1 mix of herring and pollock. Regardless of diet, retention time decreased approximately 40% as intake quadrupled. The mean apparent digestible dry matter (ADDM) was greatest on mixed diets during low feeding frequency trials; ADDM during high feeding frequency trials was significantly reduced as intake increased for animals on the single-species (pollock or herring) diets. As intake increased, up to 45% more digestible energy was assimilated from the mixed diet than from either single-species diet. The findings of this study suggest that a mixed diet consisting of prey differing in lipid and protein amounts increased digestible energy intake in harbour seals. Our measures of intake and ADDM in harbour seals revealed digestive flexibility and indicated that digestion in harbour seals was more efficient on a mixed diet.

scholarly journals Sustainable exploitation of temperate fish stocks

2009 ◽  
Vol 6 (1) ◽  
pp. 124-127 ◽  
Author(s):  
Henrik Sparholt ◽  
Robin M. Cook
Keyword(s):  
Species Interactions ◽  
Fishery Management ◽  
Regional Scale ◽  
Single Species ◽  
Fishing Effort ◽  
Theoretical Concept ◽  
Maximum Sustainable Yield ◽  
Production Model ◽  
The Status ◽  
Long Time

The theory of maximum sustainable yield (MSY) underpins many fishery management regimes and is applied principally as a single species concept. Using a simple dynamic biomass production model we show that MSY can be identified from a long time series of multi-stock data at a regional scale in the presence of species interactions and environmental change. It suggests that MSY is robust and calculable in a multispecies environment, offering a realistic reference point for fishery management. Furthermore, the demonstration of the existence of MSY shows that it is more than a purely theoretical concept. There has been an improvement in the status of stocks in the Northeast Atlantic, but our analysis suggests further reductions in fishing effort would improve long-term yields.

Marine ecosystem assessment in a fisheries management context

2002 ◽  
Vol 59 (9) ◽  
pp. 1429-1440 ◽  
Author(s):  
Jason S Link ◽  
Jon K.T Brodziak ◽  
Steve F Edwards ◽  
William J Overholtz ◽  
David Mountain ◽  
...  
Keyword(s):  
Fisheries Management ◽  
Marine Ecosystem ◽  
Single Species ◽  
Reference Points ◽  
System Level ◽  
Multivariate Statistical Methods ◽  
Multivariate Statistical ◽  
Management Context ◽  
Ecosystem Level ◽  
Ecosystem Based Fisheries Management

We examined a suite of abiotic, biotic, and human metrics for the northeast U.S. continental shelf ecosystem at the aggregate, community, and system level (>30 different metrics) over three decades. Our primary goals were to describe ecosystem status, to improve understanding of the relationships between key ecosystem processes, and to evaluate potential reference points for ecosystem-based fisheries management (EBFM). To this end, empirical indicators of ecosystem status were examined and standard multivariate statistical methods were applied to describe changes in the system. We found that (i) a suite of metrics is required to accurately characterize ecosystem status and, conversely, that focusing on a few metrics may be misleading; (ii) assessment of ecosystem status is feasible for marine ecosystems; (iii) multivariate points of reference can be determined for EBFM; and (iv) the concept of reference directions could provide an ecosystem level analog to single-species reference points.

Eggersanthus Sittichaya & Smith gen. nov., a new Oriental ambrosia beetle genus (Coleoptera: Curculionidae: Scolytinae: Xyleborini)

Zootaxa ◽  
2020 ◽  
Vol 4779 (2) ◽  
pp. 282-288
Author(s):  
WISUT SITTICHAYA ◽  
SARAH M. SMITH
Keyword(s):  
New Genus ◽  
Single Species ◽  
Ambrosia Beetle ◽  
The Status

A new genus, Eggersanthus Sittichaya & Smith gen. nov is described from a single species, Webbia sublaevis Eggers, 1927. The taxonomic characters of Eggersanthus and the morphologically similar genus Arixyleborus are analyzed and compared, and the status of the Webbia genus group is discussed. 

A molecular phylogeny of Callianassidae and related families (Crustacea : Decapoda : Axiidea) with morphological support

2020 ◽  
Vol 34 (2) ◽  
pp. 113 ◽  
Author(s):  
Rafael Robles ◽  
Peter C. Dworschak ◽  
Darryl L. Felder ◽  
Gary C. B. Poore ◽  
Fernando L. Mantelatto
Keyword(s):  
Bayesian Analysis ◽  
Molecular Analysis ◽  
Single Species ◽  
Molecular Data ◽  
Total Evidence ◽  
Morphological Data ◽  
12S Rrna ◽  
New Genera ◽  
Key Species ◽  
The Family

The axiidean families Callianassidae and Ctenochelidae, sometimes treated together as Callianassoidea, are shown to represent a monophyletic taxon. It comprises 265 accepted species in 74 genera, twice this number of species if fossil taxa are included. The higher taxonomy of the group has proved difficult and fluid. In a molecular phylogenetic approach, we inferred evolutionary relationships from a maximum-likelihood (ML) and Bayesian analysis of four genes, mitochondrial 16S rRNA and 12S rRNA along with nuclear histone H3 and 18S rRNA. Our sample consisted of 298 specimens representing 123 species plus two species each of Axiidae and Callianideidae serving as outgroups. This number represented about half of all known species, but included 26 species undescribed or not confidently identified, 9% of all known. In a parallel morphological approach, the published descriptions of all species were examined and detailed observations made on about two-thirds of the known fauna in museum collections. A DELTA (Description Language for Taxonomy), database of 135 characters was made for 195 putative species, 18 of which were undescribed. A PAUP analysis found small clades coincident with the terminal clades found in the molecular treatment. Bayesian analysis of a total-evidence dataset combined elements of both molecular and morphological analyses. Clades were interpreted as seven families and 53 genera. Seventeen new genera are required to reflect the molecular and morphological phylograms. Relationships between the families and genera inferred from the two analyses differed between the two strategies in spite of retrospective searches for morphological features supporting intermediate clades. The family Ctenochelidae was recovered in both analyses but the monophyly of Paragourretia was not supported by molecular data. The hitherto well recognised family Eucalliacidae was found to be polyphyletic in the molecular analysis, but the family and its genera were well defined by morphological synapomorphies. The phylogram for Callianassidae suggested the isolation of several species from the genera to which they had traditionally been assigned and necessitated 12 new generic names. The same was true for Callichiridae, with stronger ML than Bayesian support, and five new genera are proposed. Morphological data did not reliably reflect generic relationships inferred from the molecular analysis though they did diagnose terminal taxa treated as genera. We conclude that discrepancies between molecular and morphological analyses are due at least in part to missing sequences for key species, but no less to our inability to recognise unambiguously informative morphological synapomorphies. The ML analysis revealed the presence of at least 10 complexes wherein 2–4 cryptic species masquerade under single species names.

scholarly journals A review of factors limiting recovery of Pacific herring stocks in Canada

2010 ◽  
Vol 67 (9) ◽  
pp. 1903-1913 ◽  
Author(s):  
Jacob F. Schweigert ◽  
Jennifer L. Boldt ◽  
Linnea Flostrand ◽  
Jaclyn S. Cleary
Keyword(s):  
West Coast ◽  
Positive Relationship ◽  
Pacific Herring ◽  
Zooplankton Abundance ◽  
Natural Mortality ◽  
Population Recovery ◽  
The West ◽  
Clupea Pallasi ◽  
Adequate Food ◽  
Forage Species

AbstractSchweigert, J. F., Boldt, J. L., Flostrand, L., and Cleary, J. S. 2010. A review of factors limiting recovery of Pacific herring stocks in Canada. – ICES Journal of Marine Science, 67: 1903–1913. On the west coast of Canada, Pacific herring (Clupea pallasi) supported an intensive reduction fishery from the early 1930s until the collapse of all five major stocks in the late 1960s, which then recovered rapidly following a fishery closure. Despite conservative harvests, abundance has declined again recently, with little evidence of recovery. We investigated the effect of bottom-up forcing by zooplankton abundance, top-down forcing by fish and mammal predators, and the effects of sardine abundance as potential competitors on the natural mortality of the herring stock on the west coast of Vancouver Island. Herring mortality was positively related to Thysanoessa spinifera and southern chaetognaths and negatively to pteropod abundance. Estimated predation on herring decreased significantly during the years 1973–2008, with the main consumers changing from fish to mammals. However, the correlation with herring mortality was negative, whereas there was a significant positive relationship with sardine abundance. Population recovery is expected to be facilitated by a combination of factors, including adequate food supply, limited or reduced predation (including fishing), and limited competition particularly for wasp–waist systems, where different forage species may occupy similar niches.

Sign in / Sign up

Export Citation Format

Share Document