From data compilation to model validation: comparing three ecosystem models of the Tasman and Golden Bays, New Zealand.

The Tasman and Golden Bays (TBGB) are a semi-enclosed embayment system in New Zealand that supports numerous commercial and recreational activities. We present three ecosystem models of the TBGB ecosystem with varying levels of complexity, aimed at contributing as tools to aid in understanding this ecosystem and its responses to anthropogenic and natural pressures. We describe the process of data compilation through to model validation and analyse the importance of knowledge gaps with respect to model dynamics and results.

The impact of fishing on a highly vulnerable ecosystem, the case of Juan Fernández Ridge ecosystem.

The Juan Fernández Ridge (JFRE) is a vulnerable marine ecosystem (VME) located off the coast of central Chile formed by the Juan Fernández Archipelago and a group of seamounts. This ecosystem has unique biological and oceanographic features, characterized by: small geographical units, high degree of endemism with a high degree of connectivity within the system. Two fleets have historically operated in this system: a long term coastal artisanal fishery associated with the Islands, focused mainly on lobster, and a mainland based industrial demersal finfish fishery operating on the seamounts which is currently considered overexploited.

Biogeography and historical demography of the Juan Fernandez Rock Lobster, Jasus frontalis (Milne Edwards, 1837).

The genetic structure of present-day populations has been highly affected by glacial periods and physical oceanographic forcing, particularly with respect to species distributions and population gene-flow patterns. We assessed the current genetic composition of the Jasus frontalis population in the southeastern Pacific Islands off the coast of Chile to evaluate their connectivity modulated by contemporary and historic oceanographic processes. Population structure and demographical history for this species were assessed based on classic and Bayesian approaches using 84 sequences of cytochrome oxidase subunit I.