Versuche mit einem modifizierten Rollengeschirr für Garnelenbaumkurren

With a traditional roller gear, only the rollers in the centre are working correctly. The rollers on both sides are more or less gliding on the sea bottom because their axis are not in a position perpendicular to the towing direction. Sediment is stirred up by these gliding rollers coupled with a negative bottom impact of this gear. With a modified roller gear for shrimp beam trawls the axis of all rollers are orientated 90° to the towing direction enabling all rollers to roll correctly on the sea bottom.

Application of Suction-cup-attached VHF Transmitters to the Study of Beluga, Delphinapterus leucas, Surfacing Behavior in Cook Inlet, Alaska

Suction-cup-attached VHF radio transmittes were deployed on belugas, Delphinapterus leucas, in Cook Inlet, Alaska, in 1994 and 1995 to characterize the whales' surfacing behavior. Data from video recordings were also used to characterize behavior of undisturbed whales and whales actively pursued for tagging. Statistics for dive intervals (time between the midpoints of contiguous surfacings) and surfacing intevals (time at the surface per surfacing) were estimated. Operations took place on the tidal delta of the Susitna and Little Susitna Rivers. During the 2-yr study, eight whales were successfully tagged, five tags remained attached for >60 min, and data from these were used in the analyses. Mean dive interval was 24.1 sec (interwhale SD=6.4 sec, n=5). The mean surfacing interval, as determined from the duration of signals received from the radio transmitters, was 1.8 sec (SD=0.3 sec, n=125) for one of the whales. Videotaped behaviors were categorized as "head-lifts" or "slow-rolls." Belugas were more likely to head-lift than to slow-roll during vessel approaches and tagging attempts when compared to undisturbed whales. In undisturbed groups, surfacing intervals determined from video records were significantly different between head-lifting (average = 1.02 sect, SD=0.38 sed, n=28) and slow-rolling whales (average = 2.45 sec, SD=0.37 sec, n=106). Undisturbed juveniles exhibited shorter slow-roll surfacing intervals (average = 2.25 sec, SD=0.32 sec, n=36) than adults (average = 2.55 sec, SD=0.36 sec, n=70). We did not observe strong reactions by the belugas to the suction-cup tags. This tagging method shows promise for obtaining surfacing data for durations of several days.

Food and nutrition security in Solomon Islands

This report is a literature review on Food and Nutrition Security in Solomon Islands, based on data from surveys conducted by Solomon Islands National Statistical Office, as well as from national and international organizations working in Solomon Islands. The purpose of the report is to present information outlining the current food and nutrition situation in Solomon Islands before implementation of the CGIAR Research Program on Aquatic Agricultural Systems (AAS), led by WorldFish. The aim of the AAS program is to enhance production in natural freshwater and/or coastal ecosystems to improve household livelihood, including income and food security. This report summarizes national statistics and also focuses in more detail on a subset of provinces: Guadalcanal, Malaita and Western. In 2012, the AAS program was rolled out in Guadalcanal, Central and Malaita Provinces, designated the Central Hub. In 2013, roll out is beginning in the Western Hub (Western and Isabel Provinces). The priority province for the Central Hub has been identified as Malaita.