Climate changes in the Arctic may have important consequences for the breeding of Arctic birds, though few studies are available to evaluate the possible e#ects. I studied the breeding phenology of kittiwakes (Rissa tridactyla) breeding at two colonies (Krykkjefjellet and Ossian Sarsfjellet) in Kongsfjorden, Svalbard (13 N). Eleven years of data (in the period +31* ,**+) from Krykkjefjellet showed no longterm temporal trend in the timing of hatching. The spread of the median hatching date among the years was +. days. The median hatching date was negatively correlated with the local average April ambient temperature. Correlation analysis with largescale climate indices showed that the time of hatching was negatively correlated with the Scandinavia index in late winter (February and March), and slightly (but not statistically significantly) negatively correlated with the NAO (North Atlantic Oscillation) winter-index. A similar analysis of the number of breeding kittiwakes in study plots at Ossian Sarsfjellet showed a positive correlation between the number of breeders and average local March temperatures. These observations indicate that the kittiwakes may be able to adjust their spring arrival and breeding phenology to local or large-scale climate variations. key words: climate change, Svalbard, kittiwake, breeding phenology, North Atlantic
High latitude ecosystems were thought to enhance CH. emission in relation to the current arctic warming. However, we have little information about this potential feedback mechanisms on climate change, thus, model parameterization is insu$cient and the observational data are required. We observed CH. flux at several types of tundra in Alaska over the growing seasons since +33/. From these observed data, we examined current CH. emission and its controlling factors on Alaskan tundra. Then we discussed about spatial and temporal di#erences in CH. flux. Daily trend of half hourly CH. flux had little relation with soil temperature, but the seasonal trend of daily flux changed with soil or water temperature. Cumulative CH. fluxes during the growing seasons were 2.+ gCH.m , on wet sedge tundra at Happy Valley in +33/, -.gCH.m , on non-acidic moist tundra in +330, and -./2 2.,. gCH.m , on wet sedge tundra at Barrow between +333 ,**-. Non-acidic tundra had low CH. emission with low CO, accumulation. There was large spatial di#erence in CH. flux caused by tundra type, and the large temporal di#erence at the wet sedge tundra reflected yearly weather variability. key words: Arctic ecosystem, CH. flux, temporal and spatial variability, tundra, warming climate
Fishes thriving in polar habitats offer many opportunities for comparative approaches to understanding protein thermal adaptations. Investigations on the remarkable evolutionary adaptations to these environments of basic proteins such as hemoglobin, the oxygen carrier, can provide new insights into the mechanisms studied in temperate organisms and can shed light on convergent processes evolved in response to thermal adaptations. At the molecular level, hemoglobins are one of the most intriguing systems for studying the relationships between environmental conditions and adaptations. This review summarizes the current knowledge on molecular structure, biological function and phylogeny of hemoglobins of fish species living in both polar habitats but having different evolutionary histories. In benthic, non-migratory, cold-adapted fishes, the stability of thermal conditions may have generated no or few variations in selective pressures on globin sequences through evolutionary time, so that sequences retain the species phylogenetic “signal”. In pelagic, migratory, cold-adapted or temperate fishes, variations in selective pressures on globin sequences caused by variations in temperature accompanying the dynamic life style may have disrupted the phylogenetic “signal” in phenetic trees.
By using a general circulation model, we examine behavior of the migrating semidiurnal tide for solar cycle moderate and geomagnetically quiet conditions. We investigate day-to-day variabilities of the migrating semidiurnal tide in the mesosphere and thermosphere and their relation with the migrating semidiurnal tide generated in the lower atmosphere. The results show that day-to-day variations of the migrating semidiurnal tide are evident from the tropopause to the thermosphere. Fluctuations of the migrating semidiurnal amplitude with periods of +* +, and ,/ days are found at altitudes from ,* to ,/* km, indicating dynamical coupling between the mesosphere and thermosphere and the lower atmosphere. key words: semidiurnal tide, dynamical coupling, general circulation model
The results of monitoring acid precipitations showed that subacidalkalescent precipitations, acidity of which varies in close limits (pH /.23 1.-0) prevail in Yakutsk region. Acidity of solid precipitation is very similar to acidity of rain precipitations and comprises 0.1* 1.,, for operating pH of rain precipitations (0.2/ in average) and /.23 1.-0 for solid precipitations (0.1+ in average). The most considerable deviations of acidity-alkalinity of solid precipitation from the average value are observed at the beginning and in the middle of winter period. According to the monitoring results we made an evaluation of the value of chemical components fall-out in atmospheric precipitations. Annual inflow of H ions from atmosphere to the earth surface is much less then critical load for the forest and water ecosystems. Maximal values of sulfur compounds (*./+ g/m) and nitrogen (,.*1 g/m) fall-out at the monitoring station fall on June and exceed ecostandard and parameters of ecological emergency situation in a volume of nitrogen precipitations. key words: Yakutia, atmospheric, acid precipitations, monitoring
Half-daily high volume aerosol particles samples have been collected onto cellulose and glass fiber filters at Ny-Alesund, Svalbard, from April 14th to May 7th 2004, in the framework of CHIMERPOL II program. The filters have been analyzed for ^(210)Pb (22.3y) and ^7Be (53 d) by semiconductor gamma spectrometry. The median concentration values were 70μBq m^(-3) STP (8-264μBq m^(-3)STP) for ^(210)Pb, and 404μBq m^(-3)STP (35-824μBq m^(-3)STP) for ^7Be respectively. The ^7Be and ^(210)Pb activity concentrations measured are relatively compared to those measured in Svalbard and in other Arctic sites for the same period time (April-May) during previous studies. The ^(210)Pb atmospheric concentration and atmospheric pressure are positively correlated, which may indicate that the ^(210)Pb atmospheric concentration increase as a function of air mass exchange over the Svalbard region. The results of ^7Be and ozone concentrations show also the absence of direct ^7Be stratospheric injections during our sampling campaign, in the low troposheric air masses. The performed backward trajectory analysis showed that collected aerosols and associated radionuclides concentrations were associated to three different air masses, originating from Atlantic ocean, Artic ocean and Barents Sea, and continental areas (North Finland-Russia) respectively.
The aim of these studies was to determine local movements of hunting white sharks (Carcharodon carcharias) near a seal rookery and global movements during migra- tion. Seven adults were monitored locally with attached ultrasonic tags that received and telemetered animal position and behavior via an array of three-acoustic-positioning (RAP) buoys moored off Ano Nuevo Island, California. Migratory movements of 6 adults departing this island and nearby Southeast Farallon Island were tracked for 2-6 months with attached pop-up satellite archival tags. Sharks began hunting seals at Ano Nuevo Island in October, spending 40% of the day patrolling the 1 km 2 receptive field within 400 m of the island at a depth of 30 m or less. For six weeks, they did not stray far or long from the area, were equal- ly active at night as by day, were non-territorial, and fed infrequently. This nearshore phase at both island rookeries ended abruptly in winter as the sharks moved offshore to a region of the subtropical eastern Pacific halfway to Hawaii. An adult male went further, traveling to Hawaii where it remained until migrating back to California, only to repeat the journey the following year. Electronic tagging provides vital information on the hunting and migratory behavior of this apex predator.
For over 10 years, Little Leonardo has been developing digital data loggers for use in diverse research on marine animals. In this paper, the authors give an overview of Little Leonardo digital data loggers, the difficulties of designing a digital data logger and the possibilities for future improvements. Current data loggers are adequate to monitor animals in the field but several improvements are needed and the performance of Little Leonardo log- gers will improve as future technologies are incorporated.
There is a unique diversity and density of land-based marine predators breeding at Bird Island, South Georgia, operating at a wide variety of spatial and temporal scales. These provide exceptional opportunities for bio-logging studies, the objectives of which have been to investigate trophic interactions in ecosystem contexts (including applications in fish- eries and environmental management and conservation). Associated data from studies on feeding ecology, reproductive performance and population dynamics provide valuable con- textual information for bio-logging analyses. An associated ship-based offshore marine sci- ence programme also provides vital information about the local and regional biological and physical environment, which is both complex and highly variable. Further developments of our bio-logging studies at South Georgia face a number of important challenges. These include: • acquiring samples large enough for statistical analysis; • replicating study sites and/or populations in order to characterize population and species behaviour; • collecting simultaneous data from multiple sensors or devices in order to interpret foraging behaviour; • acquiring key collateral data on prey and environment at appropriate spatial and temporal scales to understand foraging dynamics in context. We illustrate approaches to address some of these challenges from recent studies of the South Georgia marine ecosystem.
Using satellite tracking, we have followed the movements of large wetland birds in Asia for more than 10 years. We have investigated the migration patterns of more than 10 species of birds, focusing on, but not limited to, cranes (Gruidae) and storks (Ciconiidae). To relay bird locations, we employed platform transmitter terminals in combination with ARGOS satellites. Location data were then utilized in a variety of applications, from deter- mining migration routes, stopover patterns and wintering sites, through more advanced analyses including using various data overlays to examine habitat use, occupation of nature reserves, differential migration patterns between adults and juvenile birds, climatological effects on migration and the connectivity and network structure of migration pathways. Through this work, we have identified numerous important sites for migratory birds, espe- cially cranes and storks. These include Bohai Bay and the Yellow River delta (China), the Korean Demilitarized Zone, Lake Khanka (Russia/China), and Poyang Lake, the Qiqihar Baicheng area, the Three Rivers Plain and Yangcheng Nature Reserve (all in China). We have also developed recommendations for spatial improvements to nature reserves, discov- ered different migration strategies in juvenile and adult birds, and a possible migration trig- ger involving temperature. We emphasize the importance of continued empirical research and development of analytical methodologies involving satellite location data. Further, we advocate the protection of habitats used by Gruidae and Ciconiidae over their entire migra- tion routes.
