Abstract:
Natural and anthropogenic disruptions in the flow of energy through
marine food webs can result in systematic changes which have implications
for ecosystem-based fisheries management. A recent biological regime shift
in the N. Benguela current has resulted in an alternate stable state in fish
abundance. Many of the depleted stocks are considered forage fish, species
of fish preyed upon by top predators like large piscivorous fish and marine
mammals. I will present three case studies which demonstrate some of the
consequences of depleted forage. I will then highlight documented and
probable changes to the N. Benguela as a result of depleted forage species.
Decreasing abundance of forage fish and increased abundances in jellyfish
could inhibit the system from returning to its previous state. In light of
these ecological changes, I will examine Namibia’s fisheries management
plan and the nation’s dependence upon its fisheries for economic
development. I offer short-term adaptive management strategies focused on
the restoration of depleted forage fish stocks, and improved development
opportunities. I also make recommendations for long-term strategies aimed
at an ecosystem-based management perspective with protections for top
predators that will likely undergo declines as a result of a lack of forage.
