Killer whales are attracted to herring fishing vessels

ABSTRACT: Marine mammals and fisheries often target the same resources, which can lead to operational interactions. Potential consequences of operational interaction include entanglements and damaged or reduced catches but also enhanced foraging opportunities, which can attract marine mammals to fishing vessels. Responsible fisheries management therefore requires detailed knowledge of the impact of these interactions. In northern Norway, killer whales Orcinus orca are frequently observed in association with large herring aggregations during the winter. We use a combination of biotelemetry and fisheries data to study if, to what extent and at what distances killer whales are attracted to fishing activity. Twenty-five satellite transmitters were deployed on killer whales at herring overwintering and spawning grounds, often near fishing vessels. Over 50% of the killer whale core areas of high usage overlapped with the fisheries core areas, and individual whales spent up to 34% of their time close to active fishing. We used a 3-state hidden Markov model to assess whether killer whale movements were biased towards fishing activities. Of the overall whale movements, 15% (CI = 11-21%) were biased towards fishing activities, with marked heterogeneity among individuals (0-57%). During periods of active fishing, whale movements were biased towards fishing events 44% (CI = 24-66%) of the time, with individual percentages ranging from 0 to 79%. Whales were more likely to be attracted when they were within 20 km. This information can be used in fishery management to consider potential consequences for fishers and whales.publishedVersio

Episodic rainfall influences the distribution and abundance of the regular sea urchin Lytechinus variegatus in Saint Andrew Bay, northern Gulf of Mexico

The distribution and abundance of Lytechinus variegatus (Lamarck) were determined at three shallow-water stations in Saint Andrew Bay, FL, in the northern Gulf of Mexico. Populations were monitored at 4-mo intervals from Aug. 1997 to Aug. 1999 along 2- X 10-m transects, with four transects at each station. In Aug. 1997 individuals ranged in size from 15- to 63-mm diameter (mean = 38 mm; density= 1.4 individuals (ind.) m-2) at Station 1 (Stations 2 and 3 were not sampled on that date). By Oct. 1997 individuals at Station 1 ranged in size from 26 to 62 mm (mean = 48 mm; density = 0.6 ind. m-2), suggesting the growth of individuals within the population. At Station 2, individuals ranged between 50 and 70 mm (mean = 59 mm; densities = 1.0 ind. m-2) and at Station 3 between 30 and 79 mm (mean= 51 mm; densities = 1.4 ind, m-2) in Oct. 1997, indicating a population with no recent recruits. A mass mortality event was observed in April 1998 and was attributed to reduced salinities resulting from above-average rainfall in the previous month. Sea urchins were absent at Stations 1 and 2, whereas at Station 3 postdisturbance recruits were smaller (mean = 28 mm) and densities lower. Sea urchin tests were also observed at beach stations proximate to Stations 1 and 2. By July 1998 the populations had partially recovered at Stations 2 and 3 (densities = 0.6 and 1.1 ind. m-2, respectively), but test diameters were small at both stations. Test diameters had increased in Dec. 1998 at Station 3 when compared with those of July, but individuals at Station 2 showed overall smaller test diameters (mean = 28 mm), and densities had decreased again, presumably after another mass mortality caused by another major rainfall in Sep. In April 1999 test diameters had decreased further at Stations 2 and 3, indicating emigration or death of larger animals. We suggest that the shallow-water Saint Andrew Bay population of L. variegatus is reduced for several years at a time by episodic heavy rainfalls. This observation emphasizes the importance of density-independent processes controlling the distribution and abundance of marine organisms

Episodic Rainfall Influences the Distribution and Abundance of the Regular Sea Urchin Lytechinus variegatus in Saint Andrew Bay, Northern Gulf of Mexico

The distribution and abundance of Lytechinus variegatus (Lamarck) were determined at three shallow-water stations in Saint Andrew Bay, FL, in the northern Gulf of Mexico. Populations were monitored at 4-mo intervals from Aug. 1997 to Aug. 1999 along 2- X 10-m transects, with four transects at each station. In Aug. 1997 individuals ranged in size from 15- to 63-mm diameter (mean = 38 mm; density= 1.4 individuals (ind.) m-2) at Station 1 (Stations 2 and 3 were not sampled on that date). By Oct. 1997 individuals at Station 1 ranged in size from 26 to 62 mm (mean = 48 mm; density = 0.6 ind. m-2), suggesting the growth of individuals within the population. At Station 2, individuals ranged between 50 and 70 mm (mean = 59 mm; densities = 1.0 ind. m-2) and at Station 3 between 30 and 79 mm (mean= 51 mm; densities = 1.4 ind, m-2) in Oct. 1997, indicating a population with no recent recruits. A mass mortality event was observed in April 1998 and was attributed to reduced salinities resulting from above-average rainfall in the previous month. Sea urchins were absent at Stations 1 and 2, whereas at Station 3 postdisturbance recruits were smaller (mean = 28 mm) and densities lower. Sea urchin tests were also observed at beach stations proximate to Stations 1 and 2. By July 1998 the populations had partially recovered at Stations 2 and 3 (densities = 0.6 and 1.1 ind. m-2, respectively), but test diameters were small at both stations. Test diameters had increased in Dec. 1998 at Station 3 when compared with those of July, but individuals at Station 2 showed overall smaller test diameters (mean = 28 mm), and densities had decreased again, presumably after another mass mortality caused by another major rainfall in Sep. In April 1999 test diameters had decreased further at Stations 2 and 3, indicating emigration or death of larger animals. We suggest that the shallow-water Saint Andrew Bay population of L. variegatus is reduced for several years at a time by episodic heavy rainfalls. This observation emphasizes the importance of density-independent processes controlling the distribution and abundance of marine organisms

Visually narrating post-colonial lives: ghosts of war and empire

This paper is about two journeys: the first through the memories of an old soldier captured by the Japanese in the Second World War; the second through the present life to which this past gave rise, in which the old soldier tends the graves of his fellow soldiers as part of his current navigation by bus and taxi of the post-colonial landscape of Hong Kong

Emplacement of inflated Pāhoehoe flows in the Naude’s Nek Pass, Lesotho remnant, Karoo continental flood basalt province: use of flow-lobe tumuli in understanding flood basalt emplacement

Physical volcanological features are presented for a 710-m-thick section, of the Naude’s Nek Pass, within the lower part of the Lesotho remnant of the Karoo Large Igneous Province. The section consists of inflated pāhoehoe lava with thin, impersistent sedimentary interbeds towards the base. There are seven discreet packages of compound and hummocky pāhoehoe lobes containing flow-lobe tumuli, making up approximately 50% of the section. Approximately 45% of the sequence consists of 14 sheet lobes, between 10 and 52-m-thick. The majority of the sheet lobes are in two packages indicating prolonged periods of lava supply capable of producing thick sheet lobes. The other sheet lobes are as individual lobes or pairs, within compound flows, suggesting brief increases in lava supply rate. We suggest, contrary to current belief, that there is no evidence that compound flows are proximal to source and sheet lobes (simple flows) are distal to source and we propose that the presence of flow-lobe tumuli in compound flows could be an indicator that a flow is distal to source. We use detailed, previously published, studies of the Thakurvadi Formation (Deccan Traps) as an example. We show that the length of a lobe and therefore the sections that are ‘medial or distal to source’ are specific to each individual lobe and are dependent on the lava supply of each eruptive event, and as such flow lobe tumuli can be used as an indicator of relative distance from source

Forging Links Between Food Chain Labor Activists and Academics

Interest in food movements has been growing dramatically, but until recently there has been limited engagement with the challenges facing workers across the food system. Of the studies that do exist, there is little focus on the processes and relationships that lead to solutions. This article explores ways that community-engaged teaching and research partnerships can help to build meaningful justice with food workers. The text builds on a special roundtable session held at the Annual Meeting of the American Association of Geographers in Chicago in April 2015, which involved a range of academic scholars and community-based activists. We present these insights through a discussion of key perspectives on collaborative research and teaching and learning as food-labor scholar-activists. We argue that despite significant gaps in the way that food movements are addressing labor issues, community-campus collaborations present an opportunity for building alliances to foster food justice. Building on our collective analysis and reflection, we point to five recommendations for fostering collaboration: connecting to personal experience; building trust; developing common strategies; building on previous community efforts; and, appreciating power differences and reciprocating accordingly. We conclude with some final thoughts on future research directions

Can a Higher Protein/Low Glycemic Index vs. a Conventional Diet Attenuate Changes in Appetite and Gut Hormones Following Weight Loss? : A 3-Year PREVIEW Sub-study

Background: Previous research showed that weight-reducing diets increase appetite sensations and/or circulating ghrelin concentrations for up to 36 months, with transient or enduring perturbations in circulating concentrations of the satiety hormone peptide YY. Objective: This study assessed whether a diet that is higher in protein and low in glycemic index (GI) may attenuate these changes. Methods: 136 adults with pre-diabetes and a body mass index of >= 25 kg/m(2) underwent a 2-month weight-reducing total meal replacement diet. Participants who lost >= 8% body weight were randomized to one of two 34-month weight-maintenance diets: a higher-protein and moderate-carbohydrate (CHO) diet with low GI, or a moderate-protein and higher-CHO diet with moderate GI. Both arms involved recommendations to increase physical activity. Fasting plasma concentrations of total ghrelin and total peptide YY, and appetite sensations, were measured at 0 months (pre-weight loss), at 2 months (immediately post-weight loss), and at 6, 12, 24, and 36 months. Results: There was a decrease in plasma peptide YY concentrations and an increase in ghrelin after the 2-month weight-reducing diet, and these values approached pre-weight-loss values by 6 and 24 months, respectively (P = 0.32 and P = 0.08, respectively, vs. 0 months). However, there were no differences between the two weight-maintenance diets. Subjective appetite sensations were not affected by the weight-reducing diet nor the weight-maintenance diets. While participants regained an average of similar to 50% of the weight they had lost by 36 months, the changes in ghrelin and peptide YY during the weight-reducing phase did not correlate with weight regain. Conclusion: A higher-protein, low-GI diet for weight maintenance does not attenuate changes in ghrelin or peptide YY compared with a moderate-protein, moderate-GI diet.Peer reviewe