Autumn Surveys Research Articles

Airborne fungal colonisation of coarse woody debris in North Temperate Picea abies forest: impact of season and local spatial scale

Coarse woody debris is important for mycodiversity in forest ecosystems, but its availability in managed stands is reduced. Leaving dead wood during felling is suggested as an option to sustain and restore the diversity. However, little is known what fungi would colonise freshly cut wood left on managed sites, and how the colonisation process is influenced by ecological factors. During summer and autumn, 120 freshly cut Picea abies stem sections over 8 cm in diameter were placed upright in mapped locations over two discrete plots separated by 100 m in a north-temperate forest. After seven weeks the sections were collected, and isolation and identification of fungi was done from their upper surfaces. In all 943 fungal strains were isolated, representing 97 species. Species richness in the summer survey was 42.5% higher than during the autumn survey. Low species similarity characterized the different seasons (Sorensen indices: S(S) = 0.36 and S(N) = 0.34) and for 21 species (22%) observation frequency was significantly affected by season. As a result, community structures in summer and autumn differed notably (z-test; P < 0.001). Species richness between the two plots differed by less than 10%, but there were 64 species (66%) found only in one of them, thus qualitative similarity was low (S(S) = 0.49). Quantitative similarity was higher (S(N) = 0.63), indicating that the dominant species colonised wood to a similar extent in both areas. Fungal community structure differed significantly among the two plots (z-test; P < 0.001). Our data showed that freshly cut CWD contributed to mycodiversity in managed north-temperate forest, providing habitats for numerous individuals from over 100 species. The fungal community within a single stand differed markedly both across small distances and over the seasons. In order to sustain and enhance mycodiversity in managed stands. coarse wood should always be left during harvesting. This study also demonstrates the importance of molecular identification and ITS sequence databases for exploring fungal diversity in natural communities.

Initial spread of an effluent and the overturning length scale near an underwater source in the northern Adriatic

The rise of an effluent emerging from the diffusers of the submarine sewage outfall of a small town (15000 PE) is numerically simulated with a model of initial dilution. Results were evaluated using the vertical distribution of faecal coliforms that were analyzed for two field surveys at the central position. In addition to that, the overturning length scale was calculated from vertical profiles of temperature, salinity and density. These were obtained from two autumn surveys using fine-scale CTD casts in the sewage near-field around the diffusers which lie on a flat seabed in a shallow sea. Indications that a turbulent effluent could manifest itself with a local maximum of the overturning length scale are discussed. The depth of the subsurface local peak of the overturning length scale, calculated from the density profile in the core of the sewage near-field, matches the position of the peak of the vertical distribution of faecal coliforms and the height of the simulated plume rise. The 3D space distribution of the overturning length scale indicates a structure with enhanced overturning activity below the surface mixed layer over an area of 1 km 2 which could be attributed to an effluent that erupts turbulently from diffusers.

Comparison of growth and condition indices of juvenile flatfish in differentcoastal nursery grounds

Coastal and estuarine ecosystems in the eastern channel and southern bight of the North Sea provide nursery habitats for juvenile fishes. We examined the age 0-group juveniles of three flatfish speciesSolea solea, Limanda limanda and Pleuronectes platessa, collected in five nursery areas with different characteristics (three sites located near small estuaries and two affected by important inputs of industrial effluents), to evaluate habitat influence on their growth and condition. We measured a biochemical index (RNA:DNA ratio), a morphometric index (Fulton’s K condition index), plus a recent growth index (marginal otolith increment width) on each individual (about 3 months old), collected during surveys in autumn 1999. The three indices displayed few significant differences among the five nursery sites and different patterns for each species. We suggest that the investigated nursery areas provide habitats of equivalent quality for the age 0-group juvenile flatfishes in spite of different anthropogenic disturbances. On the other hand, this study focuses on the importance of using different biological indicators to assess habitat quality and environmental stressors in coastal areas.

Is the lesser spotted dogfish (Scyliorhinus canicula) population from the Cantabrian Sea a unique stock?

Abstract A summary of the information recorded from tagging surveys since 1993 for Scyliorhinus canicula in the southern part of the Bay of Biscay (ICES Division VIIIc) is presented. In total 6619 specimens were tagged, with the recapture rate being around 2.3%. The maximum distance recorded was 158.9 miles, while 70% of the specimens recaptured were within less than 15 miles and 56% less than 10 miles. From these data, a priori, we can affirm that this species remains in certain areas, making short movements. No differences were found between males and females and no seasonal pattern was detected. Apparently, there was no relation between time at liberty and distance covered. Spatial and bathymetric distribution of both juveniles and adults are presented and combined with previous data to describe the habitat of this species. The distribution of S. canicula is continuous along the continental shelf although they may aggregate by sex and/or size. Juveniles are mostly found in the southern corner of the Bay of Biscay at depths around 200 m, while adults have a wider depth distribution (50–450 m). The temperature distribution in the study area ranged from 11 to 18 °C in the autumn surveys. Juveniles were usually found in waters around 12 °C, while adults were more abundant in waters around 14–15 °C.

The dynamics of hunted Icelandic goose populations: a reassessment of the evidence

Summary Migratory geese are dominant terrestrial herbivores in Arctic and north temperate regions. They are important quarry species and also conflict with agricultural interests through winter foraging. We investigated the dynamics of the populations of greylag Anser anser and pink‐footed Anser brachyrhynchus geese that breed in Iceland and winter in Britain. We estimated seasonal and annual survival of both populations based on colour‐ringing programmes in Iceland 1996–2000 and in Britain since 1987. We used these results, along with hunting bag statistics from Iceland, in a set of models to assess the British autumn counts as well as the impact of hunting. After a rapid increase, the pink‐footed goose counts stabilized after 1992 at around 230 000. The greylag goose counts increased slowly to c. 100 000 around 1990 and then declined to around 80 000. Both populations showed stable counts from 1996 to 2000, when the proportion of young recorded in autumn was 17·5% for greylag geese and 18·2% for pink‐footed geese. Hunting bag statistics have been compiled since 1995 in Iceland; during 1996–2000, means of 36 608 greylag geese and 13 991 pink‐footed geese were reported shot annually. Mean annual adult and first‐year survival estimates were 0·727 and 0·472 for greylag geese, and 0·814 and 0·394 for pink‐footed geese. The lower survival of juvenile pink‐footed geese was probably due to higher natural mortality, whereas the generally lower survival of greylag geese could be explained by higher hunting pressure. Simple modelling showed that the results from autumn surveys and bag statistics were incompatible for greylag geese. For the population to remain stable with the estimated survival rate, the proportion of juveniles in autumn must be 30%. We suggest that problems in separating juveniles from adults in October–November caused the lower proportion of juveniles recorded. Also, the number of greylag geese counted in autumn and the number reported shot in Iceland cannot both be correct; the bag statistics imply a population twice as large as the number counted. Large numbers of greylag geese may winter in areas not covered by the autumn census, but overreporting of the hunting bag may also have occurred. No such discrepancies were found for pink‐footed geese. Synthesis and applications. We recommend that a stratified sampling programme be established for estimating the size and age composition of both goose species. The age composition of greylag geese can profitably be studied in Iceland in August, when juveniles are easily recognizable. Ringing should be continued as a tool for monitoring survival, and a hunting bag survey should be implemented in Britain. In general, the reliability of population surveys should always be tested with independent data.

Fish assemblage structure in the East China Sea and southern Yellow Sea during autumn and spring

Based on bottom trawl surveys in autumn 2000 and spring 2001, the fish assemblage structure in the southern Yellow Sea and the continental shelf of the East China Sea was analysed. Four groups of fishes were identified for each season by the two‐way indicator species analysis (TWIA). Although seasonal migration caused a slight difference in fish assemblages between autumn and spring, two major groups of fishes, corresponding to the Yellow Sea and East China Sea were identified. Inshore and offshore groups were subsequently separated. Changes in water depth may be most important in the separation of the groups in the offshore waters of the East China Sea. Temperature affected the groupings between north and south, particularly in the central part of the Yellow Sea. Here, the cold water mass affected the species composition which was low in diversity and different from the other areas.

Spatial and temporal distribution and abundance of European hake, Merluccius merluccius, eggs and larvae in the Catalan coast (NW Mediterranean)

Plankton hauls were conducted on five surveys from November 1998 to November 1999 to study the spatial distribution of eggs and larvae of European hake off Catalonia (NW Mediterranean Sea). Also CTD casts to record hydrographic parameters were carried out on a closely spaced station grid. Merluccius merluccius eggs and larvae appeared mainly in late spring, summer and autumn surveys and were very scarce in winter. Strong differences in terms of egg and larval densities were observed between the two November surveys, which could be attributed to the anomalous hydrographic situation during November 1998. M. merluccius egg and larvae were mainly distributed over the continental shelf, with peak abundances between the 100 m isobath and the edge of the shelf. On the evidence of larval size frequency distributions in the different sampling sectors and the closely overlapping distribution patterns for the eggs and the adult spawning stock, drifting of hake eggs and larvae was not a major factor. The larval distribution extended only slightly further offshore than the egg distribution. Using the hydrographic information and the larval distribution data, an attempt was made to relate the different seasonal productivity levels over the spawning period and the distribution of the larvae.

Use of Small Caves by Ozark Big-eared Bats(Corynorhinus townsendii ingens) in Arkansas

Abstract The Ozark big-eared bat (Corynorhinus townsendii ingens) is an endangered subspecies currently known only from small populations in Arkansas and Oklahoma. Between October 1998 and May 2000 we surveyed 93 small caves in northwestern Arkansas six times. During these surveys we encountered Ozark big-eared bats in 8–10 caves every season. During surveys in spring, summer and autumn, we encountered mainly lone individuals, while up to seven individuals were encountered together during winter surveys. Winter encounters were mainly in limestone caves, particularly those with vertical or near vertical sinkhole entrances, whereas caves with more varied characteristics were used in other seasons. Temperature may also have been a factor in choice of caves, with colder caves being preferred, especially in winter. Our data indicate that Ozark big-eared bats use many small caves in the study area. These caves should be protected, and other groups of small caves in the Ozarks should be surveyed for Ozark big-ea...

A procedure to evaluate the effect of lag-time in studying length structure and growth rate of young fish: the case of &lt;i&gt;Phycis blennoides&lt;/i&gt; Brunnich, 1768 (Osteichthyes: Gadiformes) in the Central Mediterranean

The joint analysis of data from different programs represents a good opportunity to improve knowledge about the condition of any exploited populations. This note investigates the influence of lag-time in sample characteristics (growth rate and recruitment) by following a simple and quick exploratory procedure. In order to illustrate this approach, the Greater Fork-beard (Phycis blennoides Brunnich, 1768), a species with discrete recruitment pattern and available to the capture process in the first years of life, was considered . The length-frequency distributions (LFD), obtained during five spring (MEDITS - International) and successive autumn (GRUND - Italian) bottom trawl surveys, conducted from 1994 to 1998, in the Strait of Sicily and Southern Tyrrhenian Sea (Mediterranean) were analysed. The procedure was divided into three steps. Firstly, the LFD were analysed in order to estimate the mean length of the first component in each survey. Secondly, for each survey, the difference between the standardized mean lengths of the first components in the LFD of the two areas was compared with the corresponding lag-time in order to assess any systematic temporal effect in recruitment periodicity. Thirdly, for each area, the absolute and instantaneous growth rates between the spring and autumn surveys of the same year were computed on the base of the lag-time, to evaluate any difference in growth rate between the areas. The results show that the earlier the surveys begin in the Strait of Sicily, the smaller is the difference in mean length. Since the growth rates between the two areas are practically indistinguishable, the higher mean lengths observed in samples from the Strait of Sicily mainly reflect the lag-time. The reference mean growth rate found (1.03 and 0.93 cm per month in the Strait of Sicily and Southern Tyrrhenian Sea, respectively) agreed with the literature. In spring, the recruits of 0 group represent up to 90% of the whole trawl catch, and the smallest length class observed (4.5-5.0 cm) is close to the size of transition from the pelagic to the demersal one. The proposed exploratory procedure shows that systematic differences between the two investigated sub-areas in mean size and growth rate suggested by actual data are strongly reduced after having included the lag-time in the analysis.

Was over-exploitation the cause of the decline of the American plaice stock off Labrador and northeast Newfoundland?

The population of American plaice in the waters off Labrador and on the northeast Newfoundland shelf declined substantially during the mid to late 1980s, early 1990s at a time when reported catches were very low. An earlier study examined the overlap in distribution between American plaice and cod in research vessel survey data and concluded that unreported bycatch in the cod fishery could explain the decline of the Div. 2J portion of the Subarea 2+ Div. 3 K stock of American plaice. We evaluate the method proposed in that study and use reported and observer estimates of catch to investigate potential catch levels relative to survey estimates of population biomass. This method does not appear to be a good predictor of American plaice bycatch in the cod fishery as most of the regressions were not significant and it requires extrapolation well beyond the range of the data used to build the regressions. Furthermore, there was little overlap between the extent of the commercial cod fishing grounds and the distribution of American plaice in the autumn surveys. For this stock, catch to survey biomass ratios were low regardless of the source of information used to estimate catch and suggest an exploitation rate that should be well below sustainable levels. These analyses support the conclusion that fishing was not the cause of the decline in this population of American plaice.

Bottom trawl codend selectivity for cephalopods in Portuguese continental waters

Cephalopods constitute a valuable resource of Portuguese fisheries, but there are no data on the adequacy of legal mesh size with regards to minimum landing size (MLS) (or weight). In the autumn of 1998 and the spring and summer of 1999 surveys were carried out off the northern coast of Portugal to study codend selectivity of finfish bottom trawls. Mesh sizes used were 65, 80 and 90 mm (full mesh size). During these surveys primarily targeting fish species, data were obtained for the octopus, Octopus vulgaris, the European squid, Loligo vulgaris and the broadtail shortfin squid, Illex coindetii. For the octopus, selectivity parameters were estimated for the 65 mm codend ( L 50 between 8.4 and 9.7 cm and selection factor (SF) 1.3 and 1.5) and for the 80 mm codend in the summer ( L 50 14.2 cm and SF 1.9). For the European squid, selectivity parameters were estimated in the autumn survey for the 80 and 90 mm mesh size codends ( L 50 9.7 and 11.4 cm, respectively, and SF 1.3 for both codends). For the broadtail shortfin squid, selectivity parameters were estimated in the summer for the 65 mm mesh size codend ( L 50 9.5 cm and SF 1.5). Considering that the finfish bottom trawl fishery uses a minimum mesh size of 65 mm, it is concluded that a high proportion of small octopus that has a minimum landing weight (MLW) of 0.75 kg (corresponding to a dorsal mantle length of 11.8 cm) is retained. For the European squid, whose MLS is 10 cm, a 65 mm mesh size would also retain an extremely high proportion of undersized individuals, but these occur in very small numbers in the fishery. The broadtail shortfin squid has no established MLS.

Prevalence of eating disorders and weight control practices in Germany in 1990 and 1997.

To investigate whether the prevalence of bulimic behaviors and weight control practices changed between 1990 and 1997. In November 1997, we surveyed a representative sample of 2,130 adult subjects in West Germany and 2,155 subjects in East Germany. We asked subjects about binge eating, vomiting, use of laxatives, appetite suppressants and diuretics, and about dieting, weighing, and exercise. As the same questions had been used in a representative survey (N = 1,773) in autumn 1990 in West Germany, trend comparisons for prevalence between 1990 and 1997 are possible. The prevalence of severe eating binges twice a week dropped nonsignificantly between 1997 and 1990 from 3.1% to 2.4% in men and from 2.3% to 1.3% in women. In men, the prevalence of binge eating disorder dropped nonsignificantly from 2.4% to 1.5%, the prevalence of bulimia nervosa from 2.1% to 1.1%. In women, the prevalence of binge eating disorder dropped nonsignificantly from 1.5% to 0.7% and that of bulimia nervosa from 2.4% to 1.1%. The prevalence of bulimic behaviors decreased slightly during 1990 and 1997 in the West German population.

The prevalence of non‐breeders in raptor populations: evidence from rings, radio‐tags and transect surveys

Age‐specific survival and breeding (ASSAB) models were developed with data from 146 common buzzards (Buteo buteo) radio‐tagged in southern Britain during 1990–1998, in a 120‐km2 study area that had on average 25 egg‐laying pairs. Survival checks were aided by philopatric behaviour and a maximum annual tag failure rate of 7%: minimum survival rates, that were estimated by assuming death of buzzards with lost tags, were close to maximum rates that were estimated using only the recorded deaths. First‐year survival rate estimates for 35 buzzards fitted in 1990–1991 with 25–30‐g backpack radios were 69–74% (minimum‐maximum), close to the 61–71% for 16 buzzards with 12‐g tail‐mount radios; the backpacks transmitted for 2–4 yr. Overall survival rates were 66–73% in the first year, 91–97% in the second and 88–91% thereafter. Survival estimates from 288 recent British ring recoveries were lower in the first and second years, at 55% and 75%, but similar (88%) thereafter. Most deaths were from natural causes (40%) or interaction with artefacts (36%). ASSAB models, from radio‐tracking and the observed 1.71 young clutch−1, predicted breeding by 16–21% of all the buzzards present in spring, or up to 25% with the minimum likely productivity of 1.4 young clutch−1 or 12% net emigration. Ringing data predicted breeding rates of 33–38%. The models were tested with density data from nest surveys and new radio‐corrected‐transect and truncation‐mark‐resighting estimates of buzzard numbers. Surveys in autumn and late winter estimated breeding rates of 21–25%. The high non‐breeder density in spring, of three other buzzards for each paired bird with eggs, has important implications for understanding evolutionary fitness, predation and population ecology.

A study on organotin levels in Canadian drinking water distributed through PVC pipesa

A study on organotin compounds in Canadian drinking water was carried out in winter-spring 1996 (28 sites) and autumn 1996 (21 sites Approximately 29% and 40% of distribution waters supplied through PVC pipes installed recently (typically less than 6 months) contained organotin compounds in the winter-spring and autumn surveys respectively. Monomethyl-, dimethyl-, monobutyl- and dibutyltin levels ranged up to 291 ng Sn/L, 49.1 ng Sn/L, 28.5 ng Sn/L and 52.3 ng Sn/L, respectively. An additional study in summer 1996, of locations where the highest organotin levels were detected in the winter-spring survey, indicated that organotin levels had decreased in most distribution water samples. Samples of PVC pipe/tubing contained organotin compounds consistent with the organotin patterns found in the distribution water samples.

The Barents sea capelin stock 1972–1997. A synthesis of results from acoustic surveys

Abstract The abumlance of Barents Sea capelin stock has been monitored using acoustic methods since 1972. Today, 25 years later, it is one of the few stocks within the ICES area for which an annual acoustic stock size estimate serves as the only basis for stock assessment and management. The methods have changed and a large development has taken place in the technical equipment since the early 1970s. The time series of acoustic estimates from the annual autumn surveys, as well as the development of methods in the period 1972–1984 were reviewed in previous reportS. Since then, another 13 years have been added to the time series and the development of methods has continued. Some amendments and corrections have been made to the software used for calculation of stock abundance, and in the present review all stock size estimates have been recalculated. Therefore, the estimates presented here may deviate somewhat from those presented earlier. An assessment of the goodness of the acoustic stock size estimates is...

Phosphorus dynamics in a lowland river

Seasonal changes in the concentration of phosphorus and other nutrients along a section of the river Wey in southern England are reported. Measurements of the water chemistry upstream and downstream of a point-discharge together with the analysis of surface bed-sediments indicates the accumulation of phosphorus in surface sediments in the spring and summer followed by a decrease in the autumn and winter. The profiles of soluble reactive phosphorus (SRP) concentration along a stretch of river are modelled by simulating the net loss of SRP using the Elovich equation and a parabolic equation. The model utilizes results from measurements of the uptake of phosphorus by bed-sediments in a laboratory fluvarium channel. The channel was also used to measure the uptake of phosphorus and release from bed-sediments to overlying anoxic water. The measured net loss of SRP in the spring survey is much greater than expected from the uptake by the bed-sediment alone. The net phosphorus uptakes measured in the summer and autumn surveys are much less, and in closer agreement with the simulated data.

Objective derivation of macro invertebrate family sensitivity grade numbers for the SIGNAL biotic index: application to the Hunter River system, New South Wales

Chessman's SIGNAL-95 biotic index was modified on the basis of data from spring and autumn surveys of macroinvertebrates at 42 sites in the Hunter River and tributaries. An iterative algorithm was used to derive improved grade numbers reflecting the pollution sensitivities of individual families of river macroinvertebrates. The new grades were used to calculate values of the modified index (SIGNAL-HU97). These values were highly correlated with SIGNAL-95 values but were more widely spread, giving better discrimination between the sites of higher environmental quality and the more degraded sites. SIGNAL-HU97 values were also more highly correlated than were SIGNAL-95 values with environmental variables such as the conductivity of the water and a riparian, channel and environmental inventory. There was little difference in values between spring and autumn, but riffles consistently had higher mean values than other habitats.

Visual Communication Education: Cause for Concern or Bright Future?

Proposed mergers. Mergers. Threatened layoffs. Closures. While this may describe what goes on in big business, it also describes rocky couple of years journalism and mass education has experienced in 1990s. Each semester seems to bring more news about programs under review, which often means they are being looked at for possible merger with another unit or even elimination.1 According to an annual enrollment survey in Autumn 1995 Journalism Educator. Becker and Kosicki indicate that in 1994 nearly 18 percent of 430 programs in sample reported that discussion of mergers on their campuses had occurred recently, while approximately 5 percent reported discussion to eliminate their units.2 A year earlier percentages were very similar,3 and an increasing number of administrators--12.4 percent versus 9.2 percent in 1993--said they already were reporting to department head.4 For more than a dozen years future of education in journalism and mass has been debated, beginning in 1980s with Planning for Curricular Change in Journalism Education (commonly referred to as Oregon Report).5 More recently, discussion has been extended by Blanchard and Christ in Media Education and Liberal Arts: A Blueprint for New Professionalism, who argue that the 40-year-long efforts of media study programs to offer varieties of subspecialities, in response to student and media practitioner demand, have been fragmenting and sapping limited resources.6 Since those limited resources have played a key role in many, if not all, of changes being considered at journalism and mass units, we were especially concerned about fate of a subspeciality within curriculum that can be quite expensive to maintain--photojournalism and courses. Additionally, if any area of curriculum seemed ripe for continuing change because of advances in computer technology, it was in photojournalism/visual communication, so updating developments in this area of curriculum seemed timely. Changes in programs Specifically intriguing to us was anecdotal evidence that some photography programs were being eliminated primarily because units were unwilling or unable to finance switch to digital technology. For example, School of Journalism and Mass Communication at University of Wisconsin-Madison phased out all of its photography courses during early 1990s, apparently because of a lack of student interest and high cost of operating a chemical darkroom for so few students. The College of Journalism and Mass Communications at University of South Carolina stopped offering a separate photojournalism major a few years ago as well. Photojournalism courses are still taught at South Carolina, but now they are electives to print journalism, advertising and public relations majors. We think it is important for students to have an understanding of importance of communication--not just photography--and are at moment working up a new required core course on digital that will include elements of photography, on-line and data-gathering and graphic design/layout, Turk said.7 Photojournalism courses also emerged as the most frequently mentioned vulnerable course, cited by nearly one in five administrators (18.3 %) as subject most likely to be eliminated, according to a 1994 survey by Professor Doug Birkhead of University of Utah.8 Birkhead's results, published in 1995, are based on 148 responses from administrators to his questionnaire on curriculum decision making which he sent on behalf of Education Committee of American Journalism Historians Association; respondents were asked to list three courses in their undergraduate program vulnerable to elimination. When administrators were asked to identify three broad curriculum areas (beyond journalism's traditional newspaper core) and of three most vulnerable course areas, visual communication came in third (21. …

Bowhead Whales Along the Chukotka Coast in Autumn

Bowhead whales (Balaena mysticetus) were seen in autumn 1992 and 1993 only along the northern coast of Chukotka, Russia, although an extensive area of the Chukchi Sea was searched during ship cruises. Single-day counts for 76 and 50 bowheads were made on 1 October 1992 and 3 October 1993, respectively, with only a few whales seen on other days. Whales seen between Cape Schmidt and Cape Vankarem on 1 October 1992 appeared to be feeding, but there was no means to detect or sample subsurface forage that year. On 3 October 1993, bowheads appeared to be feeding in an area where a 5 m x 8 km patch of zooplankton was identified, via acoustics, at 25-30 m in water 35 m deep. A vertical-tow sample near the patch indicated the euphausiid Thysanoessa rachii, a common bowhead prey species, was abundant in the water column. The location of the zooplankton patch corresponded with a sharp salinity (proxy density) gradient. In addition, whale distribution coincided with a surface thermal boundary, identified by satellite-borne Advanced Very High Resolution Radiometer (AVHRR) imagery. The confinement of bowhead sightings to the northern coast of Chukotka in 1992-93 corresponds to reports from autumn surveys in 1979, 1980 and 1990, while the association of whales with physical oceanographic fronts is similar to findings from a study of bowhead feeding areas in the southern Beaufort Sea. These observations suggest that the Chukotka coast may be an important feeding or staging area for the Bering Sea stock and that oceanographic patterns influencing whale occurrence may be identifiable from standard oceanographic measurements.Key words: bowhead whale, Balaena mysticetus, migration, Chukchi Sea, Bering Sea, Chukotka, Thysanoessa rachii, satellite imagery, AVHRR

Changes in populations of bird species in roadside softwood scrub remnants/farmland and open eucalypt forest in south-east Queensland, 1981 to 1993

Long-term monitoring of bird species provides information on base-line populations and population trends required to ensure that habitat management is effective for their conservation. Two surveys in both spring and autumn over 12 years monitored populations at fixed points in roadside softwood scrub remnants plus adjoining farmland (softwood/farmland) and in eucalypt open forest in south-east Queensland. The main aims were to determine the status of species in each habitat, especially whether the status of any species was changing, and to assess the usefulness of the monitoring procedure. In all, 92 species were observed; 79 in the softwood/farmland and 74 in the eucalypt forest. From 49 to 56 species were observed each year in softwood/farmland and 34 to 46 in eucalypt forest. Annual species turnover in softwood/farmland was about half that in eucalypt forest; 39% of all species were observed every year in the former habitat, but only 19% in the latter. The Torresian Crow was most often observed in softwood/farmland and the Noisy Miner in eucalypt forest. The Torresian Crow was the only species to be among the five most observed in each habitat. Among other common species, 95% or more observations of Bar-shouldered Doves, Superb Fairy-wrens, Yellow Thornbills and Silvereyes were in softwood/farmland, whereas for Weebills, White-throated Gerygones, Buff-rumped Thornbills, White-throated Treecreepers and White-throated Honeyeaters at least 95% of observations were in eucalypt forest, confirming their strong habitat specificities. The number of birds observed increased linearly for eight species in softwood/farmland and six species in eucalypt forest, and decreased for five and four species, respectively, over the 12 years. The most significant trends were for the Crested Pigeon (increase) and Willie Wagtail (decrease) in softwood/farmland, while Peaceful Dove and Rufous Whistler decreased in both habitats. Several species which increased adapt well to partial clearing of woody vegetation and aggressively exclude others, e.g., Noisy Miner, butcherbirds and Pied Currawong. The trends may reflect insidious degradation of habitats. The main value of the survey method was for detecting changes of species that could be used as indicator species ? those that respond most rapidly to habitat change. While the method was efficient, wildlife managers would need to use it regularly to maintain skills, especially because most observations are of bird calls.