<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sean P. Cox</style></author><author><style face="normal" font="default" size="100%">James F. Kitchell</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Lake Superior ecosystem: sequential fisheries collapses and conflicting objectives for rehabilitation</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of Marine Science</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">Submitted</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An important goal of ecosystem modeling is to assess potential conflicts among alternative ecosystem management options. The Lake Superior ecosystem provides an excellent setting in which to test whether ecosystem models can detect ecosystem management conflicts. Overfishing and invasions by sea lamprey and rainbow smelt caused lake-wide collapses of the dominant piscivore (lake trout) and zooplanktivore (whitefish and lake herring) species. Restoration policies put a higher priority on restoring lake trout (the predator) rather than lake herring (the prey) and proceeded along a path of artificial enhancement and reduced fishing mortality for lake trout only. Although lake trout have since recovered to historical highs, the lake herring population remains at critically low levels. We developed an Ecopath with Ecosim model of the Lake Superior fish community (1929-1998) to determine the relative impacts of lake trout enhancement programs, fish community dynamics, and fishing mortality on the lake herring population. Although much of the observed variation in forage fish biomass was accounted for by the simulated dynamics of top trophic level groups, we found little evidence that any factor besides fishing could account for lake herring dynamics. Difficulty representing trophic dynamics at or near critically low population levels raises some doubt as to our ability to model and respond to important ecosystem trade-offs.</style></abstract><notes><style face="normal" font="default" size="100%">Mote Symposium 2002</style></notes></record></records></xml>