Worldwide fisheries generate large volumes of fishery waste and it is often assumed that this additional food is beneficial to populations of marine top-predators. We challenge this concept via a detailed study of foraging Cape gannets Morus capensis and of their feeding environment in the Benguela upwelling zone. The natural prey of Cape gannets (pelagic fishes) is depleted and birds now feed extensively on fishery wastes. These are beneficial to non-breeding birds, which show reduced feeding effort and high survival. By contrast, breeding gannets double their diving effort in an attempt to provision their chicks predominantly with high-quality, live pelagic fishes. Owing to a scarcity of this resource, they fail and most chicks die. Our study supports the junk-food hypothesis for Cape gannets since it shows that non-breeding birds can survive when complementing their diet with fishery wastes, but that they struggle to reproduce if live prey is scarce. This is due to the negative impact of low-quality fishery wastes on the growth patterns of gannet chicks. Marine management policies should not assume that fishery waste is generally beneficial to scavenging seabirds and that an abundance of this artificial resource will automatically inflate their populations.

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On a watershed scale, geospatial information can be used to identify water resources that are least buffered from contamination. Implementing conservation practices at these locations may accelerate the process of increasing a watershed's ability to support its designated uses. The Upper Oconee Watershed of Georgia contains land areas devoted to poultry, dairy, and beef production. Within these historically agricultural lands, urbanization is proceeding rapidly around existing cities. Agricultural production practices are concentrated in the watershed with poultry in the headwaters area and dairy near a major lake (Lake Oconee). The objective of this research was to relate data sets representing surface water quality at selected sites throughout the watershed to the predominant land use in that portion of the watershed. The location of 550 poultry operations in the headwaters of the Upper Oconee Watershed, away from the city of Athens GA, has minimized con¯icts between agricultural and urban interests. Phosphorus, nitrogen, and fecal coliform bacteria were high near the poultry production area, but were reduced within the watershed prior to reaching the intake for the municipal water supply. Athens had a large impact on surface water quality and approximately doubled the amount of phosphorus and nitrogen in the Oconee River. The Oconee River contributed approximately 70% of the water¯owing to Lake Oconee. The residents of Lake Oconee have noted the 30 dairies located west of the lake impacting two relatively minor creeks¯owing to the lake. These two creeks make up approximately 2.5% of the¯ow to the lake, but the proximity of the dairies to the lake makes losses of phosphorus, nitrogen, and fecal bacteria apparent in water samples. Fecal coliform numbers were elevated in some creeks with little agricultural or urban development. To test alternative microbial assays, surface water from a grazed watershed was compared to water from a wooded watershed. Assays for enterococci and E. coli may provide a better test for fecal contamination and allow differentiation between natural areas and areas impacted by grazing animals. Analysis of the Upper Oconee Watershed identi®ed agricultural impacts and areas that should be priorities for natural resource management to reduce agricultural nonpoint source pollution. Focusing conservation efforts at these locations may prevent agricultural±urban con¯ict. However, the data also indicate that municipal sources of nutrients and fecal bacteria must be reduced to make signi®cant progress in the watershed. #

Endophyte (Acremonium coenophialum Morgan-Jones et Gams) -infected tall fescue (Festuca arundinacea Scbreb.) produces ergopeptine alkaloids (EP) that may be associated with fescue toxicosis symptoms in cattle (Bos taurus). A study was conducted during 1983 and 1984 at Watkinsville, GA, to determine the effects of endophyte infection, season, and N fertilization on EP concentration and steer average daily gain (ADG) in grazed 0.7-ha tall fescue paddocks. Treatments included low (LF) and high (HF) endophyte infection frequency 'Kentucky-31' (KY-31) tall fescue fertilized with 134 or 336 kg N ha-• (2x2 factorial) replicated three times. The cultivars AU Triumph and Johnstone were also evaluated. Animals were managed using put-and-take grazing system. Ergopeptine alkaloid concentration (ergovaline was 80% of total) was greater in HF KY-31 than LF KY-31 in both years. Peak ergovaline concentrations occurred in spring and again in autumn (1984) when concentrations in HF KY-31 approached 1 mk kg-•. Mid-summer concentrations were about one-third the autumn maximum for HF and LF KY-31. Nitrogen fertilization bad minimal effect on ergovaline concentration in the spring-summer of 1983 but increased concentrations in LF KY-31 in 1984. Ergopeptine alkaloids were not detected in endophyte-free AU Triumph, and were detected in low amounts ( < 0.1 mg kg-1 ) in a pre-varietal release of Johnstone containing 7 to 10% endophyte. Increased ergovaline was associated with decreased ADG in the spring-summer of 1983 and 1984; however, there was no significant association between ergovaline and ADG when the entire (April-December) 1984 growing season was considered, suggesting that ergopeptine alkaloids may operate in conjunction with other environmental and nutritional factors to elicit fescue toxicosis symptoms.