Characterizing seabird bycatch in the eastern Australian tuna and billfish pelagic longline fishery in relation to temporal,spatial and biological influences

• 1. Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.
• 2. During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.
• 3. Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.
• 4. The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.
• 5. The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.

     

Woodland salamander response to two prescribed fires in the central Appalachians

Using coverboard arrays, we monitored woodland salamanders on the Fernow Experimental Forest in the central Appalachian Mountains, West Virginia, USA prior to and following two prescribed fires in mixed oak (Quercus spp.) forest stands. Treatments were burn plots on upper slopes or lower slopes fenced to prevent white-tailed deer (Odocoileus virginianus) herbivory or control plots that were unfenced and unburned. Most of the 7 species we observed were the mountain dusky salamander (Desmognathus ocropheaus), red-backed salamander (Plethodon cinereus) and slimy salamander (Plethodon glutinosis). Significant population responses were difficult to interpret with numerous treatment and year interactions. Results largely were equivocal. We found no change in woodland salamander assemblage prior to burning or afterwards. There were few differences in adult to juvenile ratios of salamanders among treatments. Still, a priori contrasts of mountain dusky salamanders and red-backed salamander counts corrected for detection probability were greater under coverboards in the 2 years monitored after both prescribed fires had occurred than before burning or in unburned controls. This suggests that these species responded to the reduced leaf litter on the forest floor by utilizing coverboards more. Similarly, the three predominate species of salamanders also were more numerous under coverboards in plots subjected to deer herbivory with less subsequent forest floor vegetation as compared to those burned plots that were fenced. Our observations would suggest that woodland salamanders somewhat are tolerant of two prescribed fires within close temporal proximity. However, because woodland salamanders can be significantly reduced following timber harvest, continued research is needed to fully understand impacts of fire as a pre-harvest management tool in central Appalachian forests.     

Danofloxacin (Advocin) reduces the spread of contagious bovine pleuropneumonia to healthy in-contact cattle

Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides SC (MmmSC), is one of the most important diseases of cattle in Sub-Saharan Africa. The live T1/44 vaccine is normally used for its control but produces only transient protection and gives rise to adverse reactions. The present study evaluated the efficacy of danofloxacin (2.5% Advocintrade mark, Pfizer Ltd.) for the treatment of naturally infected cattle and in the prevention of CBPP transmission to in-contact cattle. Adult cattle, taken from a natural outbreak, were placed into two groups of 10 animals and kept on a research farm in paddocks 50m apart. One group was treated with 2.5mg/kg danofloxacin on days 0, 1 and 2; the other group were saline treated. On day 2, 10 CBPP-free, seronegative cattle were placed in contact with each of the two groups. All cattle were monitored for 3.5 months. No differences were seen in clinical improvement of the CBPP-affected cattle treated with danofloxacin compared with the untreated CBPP-affected cattle with approximately half of each group being withdrawn because of CBPP or showing CBPP lesions at post mortem examination. Clinical scores of the two groups were also similar. However cattle kept in contact with the danofloxacin-treated CBPP-affected animals showed significantly fewer lesions, less mortality and fewer animals were seropositive (P<0.02) and had reduced clinical scores (P<0.001) compared to cattle kept in contact with untreated CBPP-affected cattle. MmmSC was also isolated from fewer contact controls kept with the treated group. These findings could have important implications for the control of CBPP in Africa.     

Effect of danofloxacin (Advocin A180) on goats affected with contagious caprine pleuropneumonia

The efficacy of danofloxacin (Advocin A180) was evaluated for the treatment of contagious caprine pleuropneumonia (CCPP) caused by Mycoplasma capricolum subsp. capripneumoniae. Ten healthy Angora goats, confirmed free of CCPP, were exposed to clinically affected animals from a natural outbreak in Thrace, Turkey. After 14 days exposure, 8 goats showed pyrexia ( > or = 41 degrees C). Shortly after, the Angora goats were divided randomly into two groups. Five of these were injected with danofloxacin (6 mg/kg subcutaneously), which was repeated after 48 h; the five remaining animals received saline. Goats were monitored clinically and blood samples were collected for serology. Animals with severe disease were withdrawn from the trial. Goats completing the study were euthanized at day 42. Lung tissue and bronchial fluid were collected for mycoplasma isolation. All danofloxacin-treated goats showed resolution of clinical disease by the end of the trial. Two saline-treated goats failed to complete the study owing to CCPP. Danofloxacin-treated goats showed fewer lung lesions and had significantly lower combined clinical scores than saline controls (p < 0.001). Danofloxacin was found to be highly effective in the treatment of CCPP in goats.     

Mapping species richness and human impact drivers to inform global pelagic conservation prioritisation

Given the widely recognized need to better protect the oceans but limited resources to do so, methods for prioritizing potential protected area sites are important. This is particularly true for the open oceans, where few protected areas currently exist and data availability is limited. Here, we examine the relationship between the distributions of tuna and billfish species richness (an indicator of pelagic biodiversity), the human impact drivers of fishing pressure (quantified as cumulative removals) and sea surface temperature increase (quantified as the increase in large positive anomalies) in tropical to temperate oceans at the scale of a 5° × 5° grid. We investigate relationships using Generalised Additive Models and Regression Tree analysis, and identify the top 50 “hotspot” cells for species richness and each of the two impact drivers. We find that both impact drivers significantly overlap with high species richness, but relationships are complex, non-linear and ocean-basin specific. Higher fishing pressure is associated with higher species richness in the Indian and Pacific Oceans, and this overlap is particularly prominent in the central Pacific, and in the Indian Ocean around Sri Lanka. In the Pacific and Atlantic Oceans, species richness is generally higher in areas that have seen lower levels of change in sea surface temperature and only one cell, near Easter Island, is a hotspot for species richness and sea surface temperature increase. While species richness and impact drivers overlap in some areas, there are many areas with high species richness and limited apparent impact. This suggests that area-based conservation strategies that aim to protect areas of high pelagic biodiversity may be achievable with limited displacement of fishing effort.     

Some observations on the effects of age of calves on the phagocytosis and killing of Staphylococcus aureus by polymorphonuclear leucocytes

The effects of age on bovine polymorphonuclear (PMN) cell function were investigated by comparing the efficiencies of phagocytosis and killing of Staphylococcus aureus by peripheral blood leucocytes sequentially obtained from 15 calves between the ages of less than 1 and 84 days. One group of seven calves was kept in a controlled environmental chamber with air temperature of 5 degrees C and 58% relative humidity (RH) and another group of eight calves was kept at 16 degrees C and 58% RH. The calves were given a diet a liquid milk substitute and dry food, and were weaned abruptly from the liquid diet at 35 days of age. The in-vitro efficiencies of phagocytosis, and of killing, Staphylococcus aureus by peripheral blood leucocytes were similar for calves in air temperatures of 5 degrees C and 16 degrees C (P greater than 0.05). Peripheral blood leucocytes obtained from calves of less than 1 day of age were more efficient in phagocytosing S. aureus than those obtained when the same calves were 14-84 days of age (P less than 0.001). Peripheral blood leucocytes obtained when the calves were 42 and 56 days of age were significantly less efficient in phagocytosing and killing S. aureus than those obtained when the same calves were less than 1, 14, 28, 70 and 84 days of age (P less than 0.001).     

Biosynthesis of straight-chain ester volatiles in red delicious and granny smith apples using deuterium-labeled precursors.

Biosynthesis of straight-chain ester volatiles by Granny Smith and Red Delicious apples was investigated using deuterium-labeled fatty acids, C-6 aldehydes, and alcohols. Perdeuterated saturated and monounsaturated fatty acids were metabolized to hexyl-d(11), hexanoate-d(11), heptanoate-d(13), and octanoate-d(15) esters, whereas perdeuterated linoleic acid produced only hexyl-d(11) and hexanoate-d(11) esters. Exposure of fruit to vapors of deuterated 3Z-hexenal, 2E-hexenal, and hexanal identified the following biosynthetic processes: (1) isomerization between 3E, 3Z, and 2E-hexenals; (2) reduction to 3E, 3Z, and 2E-hexenyl esters; (3) reduction to hexanol and hexyl esters; (4) oxidation to hexanoic acid and formation of hexanoate esters; (5) beta-oxidation of hexanoic acid leading to butyl and butanoate esters; and (6) alpha-oxidation of hexanoic acid leading to pentyl and pentanoate esters. Unsaturated straight-chain ester volatiles appear to arise only by the lipoxygenase pathway and may be useful indicators of lipoxygenase activity in fruit.