Sawdust Empire, Sawdust Mountain, and Beyond: The Challenges for the State of Jefferson, as Seen Through the Photographs of Eirik Johnson’s Sawdust Mountain

Eirik Johnson’s Sawdust Mountain portfolio of photographs explores the past, present, and possible futures of the rural Pacific Northwest including the State of Jefferson. Jefferson has been dependent on and shaped culturally and economically by logging and fishing, but these extractive industries have been transformed by technology and are declining in importance. Johnson’s photographs portray specific instances of these shifts and the uncertainties and ambiguities of the present. His photographs suggest three possible directions for Jefferson’s future. One is continued resource extraction, modified to suit contemporary attitudes and values; a second is suburbanization; and a third involves a relative retreat, leaving the area remote, and allowing nature to regrow. Johnson’s photographs allow us to experience visually the changes in and possibilities for Jefferson

Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management

Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems

Water velocity limits the temporal extent of herbivore effects on aquatic plants in a lowland river

The role of herbivores in regulating aquatic plant dynamics has received growing recognition from researchers and managers. However, the evidence for herbivore impacts on aquatic plants is largely based on short-term exclosure studies conducted within a single plant growing season. Thus, it is unclear how long herbivore impacts on aquatic plant abundance can persist for. We addressed this knowledge gap by testing whether mute swan (Cygnus olor) grazing on lowland river macrophytes could be detected in the following growing season. Furthermore, we investigated the role of seasonal changes in water current speed in limiting the temporal extent of grazing. We found no relationship between swan biomass density in 1 year and aquatic plant cover or biomass in the following spring. No such carry-over effects were detected despite observing high swan biomass densities in the previous year from which we inferred grazing impacts on macrophytes. Seasonal increases in water velocity were associated with reduced grazing pressure as swans abandoned river habitat. Furthermore, our study highlights the role of seasonal changes in water velocity in determining the length of the mute swan grazing season in shallow lowland rivers and thus in limiting the temporal extent of herbivore impacts on aquatic plant abundance

Persistence of wages, prices and output under rational expectations when the labour market is dominated by workplace bargaining

Engineering employers yesterday told union leaders that a severe decline in output would limit their ability to pay higher wages this year. The employers told the Confederation of Shipbuilding and Engineering Unions that they expected output for 1981 to drop by 17 per cent compared with 1979.