Devil rays (Mobula spp.) face intensifying fishing pressure to meet the ongoing international demand for gill plates. The paucity of information on growth, mortality, and fishing effort for devil rays make quantifying population growth rates and extinction risk challenging. Furthermore, unlike manta rays (Manta spp.), devil rays have not been listed on CITES. Here, we use a published size-at-ag...

The decline of the eastern oyster (Crassostrea virginica) as an estuarine resource is well documented for many estuaries on the United States east coast. This decline is often associated with a decline in the shell resource and ultimately the disappearance of the shell bed. We develop a model that expressly and conjointly evaluates oyster abundance and surficial shell quantity and examine wheth...

Historically, it has been difficult to balance conservation goals and yield objectives when managing multispecies fisheries that include stocks with various vulnerabilities to fishing. As managers try to maximize yield in mixed-stock fisheries, exploitation rates can lead to less productive stocks becoming overfished. In the late 1990s, population declines of several U.S. West Coast groundfish ...

The selectivity of fishing gears with respect to fish species and size is important, both for fisheries management and fishing operations. Purse seining is an efficient, environmentally friendly fish capture methodology generally targeting single species aggregations, but once a fish school has been selected and surrounded by the seine, there is no selections for individual size, species or cat...

ion6. Population connected to wastewater secondary treatment systems7. Biochemical oxygen demand in riversSub-theme: MARINE ECOSYSTEMS8. Concentration of mercury in fishand shellfish*9. Size of fishing fleet Sub-theme: LAND USE10. Land use change*, by category(proxy: Built-up areas) 11. Forest increment and fellings12. Forest trees damaged by defoliation 13. ...

In exploited fish stocks, long-term trends towards earlier maturation have been interpreted as an evolutionary response to sustained, high fishing mortality. The evidence used to support this diagnosis consists of directional shifts in probabilistic maturation reaction norms (PMRNs) that are consistent with the expectation that high fishing mortality favours the genotype for early maturation. M...

1. Industrial longline fishing has been suspected to impact upon black-footed albatross populations Phoebastria nigripes by increasing mortality, but no precise estimates of bycatch mortality are available to ascertain this statement. We present a general framework for quantifying the relationship between albatross population and longline fishing in absence of reliable estimates of bycatch rate...

Jensen, A.L., 1991. Simulation of fish population responses to exploitation. Ecol. Modelling, 55: 203-218. A model that couples Larkin's predator-prey model, Ivlev's feeding model, Ursin's growth equation and the exponential mortality model was applied for simulation of the responses of fish populations to exploitation. Simulations were done without food-limited growth, with food-limited growth...

Exploited ecosystems are characterised by exports of secondary production from each fished trophic level that reduce the energy available for upper levels at the ecosystem scale, thus impinging on overall secondary production. Depletion in secondary production is proposed here as a proxy for quantifying the ecosystem effects of fishing. Theoretical analysis of trophic web interactions permits t...

We assess the potential consequences of recent (2012) fishing conditions on the future biological status of the three tropical tuna stocks, based upon the new tropical tuna stock assessments. Projected status in 2032 is reported relative to spawning biomass and fishing mortality reference points in absolute terms (as a median of the projection outcomes) and in probabilistic terms. Here, we have...