广东沿岸海域鱼类群落排序

根据广东沿岸海域春秋两季底拖网鱼类采样数据,运用多维尺度转换分别对两季的鱼类样品进行排序。排序揭示出的鱼类群落格局及其季度差异与环境变异性密切相关。同处混合水区域的站位鱼类组成较为相似;分布在珠江冲淡水和外海高盐水区域的站位,鱼类组成则与多数沿岸站位有明显差异。春季沿岸海域鱼类组成有一东北－西南向的变化趋势,这一群落格局是由于该海域东北部受低温东海沿岸流影响所致;秋季珠江河口区受冲淡水的影响,而调     

Temporal and spatial patterns in ichthyoplankton assemblages in bay and open coastal environments

The larval fish fauna occurring in temperate bay and shelf waters off Victoria, southern Australia, was found to be diverse, comprising taxa from 52 families. The most abundant groups collected were gobiids, tripterygiids, gobiesocids and clupeids. Fish egg concentrations were highest during spring and summer (September to February). Eggs of the Australian anchovy Engraulis australis occurred mainly during spring (September to November). Total larval fish concentrations were highest during summer (December to February), and were significantly higher at 1 km than 2 and 5 km from shore in offshore samples. Larval concentrations of a number of families, mainly reef‐associated taxa that attach their eggs to hard substrata, were also higher nearer to shore. These larvae are more developed upon hatching than those of pelagic spawners and more capable of avoiding passive drift. Multivariate analyses found that larval taxonomic composition did not vary significantly with distance from shore, but that seasonal and monthly groupings were evident, with different taxa dominating at different times of the year. Larvae of the families Gobiidae and Tripterygiidae occurred in all months, but were less abundant during winter. Spatial differences in the larval fish assemblage between offshore samples and samples taken in the bay were only apparent during summer. This was primarily due to a higher abundance of seagrass‐associated species, such as syngnathids and hemiramphids, utilizing specific habitats in the bay.     

SEA-BIRDS AT LAGOS AND IN THE GULF OF GUINEA

Regular observations of sea-birds were made in the vicinity of Lagos, southwest Nigeria, between October 1967 and June 1971. Records in the Gulf of Guinea were obtained in April 1969 and, together with others from Ghana and Sierra Leone, were used to complement this study. While few large populations of sea-birds are supported, the diversity of species occurring at Lagos and over offshore deep water was great. The occurrence of nine species of sea-bird new to Nigeria was established or confirmed; most of these were also new to West Africa southeast of Gambia. Details are given of fluctuations in numbers these and a further 16 species.
All coastal habitats at Lagos supported a large population of immature Black Terns, and groups of immatures made up a high proportion of observations of other Palaearctic terns and of Royal Terns, which breed only in northwest Africa. In contrast, the Lesser Black-backed Gulls and Damara Terns reaching Lagos (from breeding grounds almost two continents apart) were mainly adults; both these species are amongst those showing a current increase in numbers. A pronounced spring passage was observed among species including Royal and Sandwich Terns, but adult movements in autumn were not elucidated. The occurrence of the European race of the Little Tern in southwest Nigeria was confirmed, it is at least a regular spring migrant. The frequency of vagrants in January and February was linked to local climate as much to general distribution. Brief comment is also given on immature plumages, and the growing exploitation and pollution of coastal waters.     

Snow goose migration phenology is related to extratropical storm climate

The phenologies of autumn and spring migrations by greater snow geese (Anser caerulescens atlantica) are shown to be statistically independent. Spring and fall migration phenologies are demonstrated to be significantly related to synoptic scale atmospheric circulation systems (extratropical storms) rather than a factor such as temperature. Interannual variation in the timing of migratory movements by snow geese reflect interannual variation in the climatology of extratropical storms. Early fall migration is significantly related to an increased frequency of cyclonic disturbances off the United States east and gulf coasts. Years in which autumn migration is delayed occur when the Atlantic coast storm track is displaced northward. Late spring migrations are related to extratropical storms being more frequent over the Great Plains, along the gulf coast, and over the northern Gulf of Mexico. Increased cyclone activity through the Ohio River valley and over the Great Lakes tends to advance the onset of spring migrations.     

An investigation of the advantages of autumn and spring stocking with brown trout Salmo trutta L. in a Yorkshire reservoir

Batches of trout have been introduced into Chelker Reservoir in Yorkshire in the autumn and spring since the 1870's for angling purposes. Six batches of tagged, hatchery-reared brown trout Salmo trutta L. were introduced from autumn 1966 to spring 1969. During the angling season fish introduced in the spring give better catches than those stocked in the autumn. At the beginning of the season the larger fish in the spring batch are caught more often than the smaller fish from the same batch. The larger fish in the autumn batch are caught more often than the smaller fish from that batch throughout the season. The population, available to the angler from the shore was estimated to be 1491 in 1968, with 722 fish/km of shoreline. More fish survive to a second year in the reservoir than is apparent from the number of tags returned. Fish introduced in the spring usually begin growing before those introduced in the autumn, thereafter growth rates varied. The growth rate was independent of the number offish stocked up to the numbers put in.
Batches of tagged trout were retained at the hatchery up to nine months to gain relevant experience of post-tagging mortalities, tag loss rate and effect of tags on growth.     

Latitudinal trends, population size and habitat preferences of the Damara Tern Sterna balaenarum on Namibia's desert coast

The Damara Tern Sterna balaenarum is a rare, near-endemic breeder along the southwestern coast of Africa. Found predominantly in Namibia, its world population was once believed to be 4000 birds. Population surveys in the northern Namib Desert have recently estimated that 12,000 adults exist. The aims of this study were to (1) determine the population status along the southern coast, thereby completing Namibian surveys, (2) assess latitudinal trends (over 10̀) in relation to ocean upwellings for the entire coast and (3) determine breeding habitat preferences. This was completed in 1994 and 1996 using random sampling techniques. Survey squares of 1 km², randomly plotted on 1:50,000 maps, were located in the desert with a Global Positioning System (GPS) unit and searched for breeding terns. A total of 1780 km² was sampled in the southern desert and extrapolations indicated that about 1450 adult terns occur in this region. This gives a global population estimate of 13,500 adult Damara Terns. Significant habitat preferences were apparent with terns nesting most often on gravel plains in the north but switching to salt pans in the south. Lower salt pan temperatures in the south may account for these trends. The peak density was in central areas (23|dGS) with a decreasing density north and south along Namibia's 1470 km-coast. This is parallel to recent findings for linear shorebird densities and macro-invertebrate density. This suggests that primary productivity of the Benguela is highest in the central regions and not where the upwellings occur 400 km south. We propose a delayed blooming effect to account for these trends and conclude that this diminutive tern is influenced in many aspects of its life history by Namibia's cold offshore upwellings.     

Sea trout in North Argyll Sea lochs, population, distribution and movements

Sea trout were sampled by shore seining in the sea lochs of the west coast of Scotland between 1970 and 1974, This area is of special interest because of the indentation of the coastline and the varying degree of freshwater and marine influence in the sea lochs. The majority of fish caught were in their first year after smolt migration. These post-smolts were caught mainly in May and June, after which the number of trout present was low until fish at the 'whirling' stage appeared in the catches at the end of August, continuing through to the following spring. An additional recruitment of mainly unsilvered young trout from the rivers to the sea lochs was found in the autumn. Age and sex composition of both spring and autumn recruits, and of mature fish, were investigated and compared.
A total of 3228 sea trout were tagged, with 311 recaptures. These recaptures supported the evidence from smolt trapping and beach seine catches that, in the first post-migration year, the smolts migrate from the rivers from late March to early May, they then migrate from the sea lochs in May and June and return in late summer and autumn.     

黄海山东海域春、秋季鱼类群落多样性

根据2006年春季(5月)和秋季(10月)黄海山东海域疏目变水层双拖网调查数据,作者对该海域鱼类群落多样性、空间分布及长度谱特征进行了研究。调查共捕获鱼类61种,其中鲈形目种类最多(27种),其次为鲱形目(8种)和鲉形目(7种);按摄食类型可分为浮游动物食性、浮游动物/底栖动物食性、底栖动物食性、底栖动物/游泳动物食性、游泳动物食性、杂食性、碎屑食性7个类群,其中浮游动物食性占渔获物重量组成的82.5%。春、秋季鱼类群落均主要由小型种类占优势,春季优势种有3种,为玉筋鱼(Ammodytes personatus)、鳀(Engraulis japonicus)和方氏锦鳚(Pholis fangi),秋季优势种有5种,分别是鳀、青鳞小沙丁鱼(Sardinella zunasi)、玉筋鱼、小黄鱼(Larimichthys polyactis)和赤鼻棱鳀(Thryssa kammalensis)。丰富度指数(D)、Shannon-Wiener多样性指数(H’)、均匀度指数(J’)的空间异质性明显,表现出近岸海域(尤其是青岛-乳山南部近岸海域)较高,深水区较低的态势,但多样性指数的季节间差异不显著。资源量与Shannon-Wiener多样性指数(H’)、均匀度指数(J’)、功能团多样性指数(FD)均呈负相关关系,与种类丰富度指数(D)则无相关关系。春、秋季鱼类群落长度谱曲线斜率均小于-0.2,而截距均大于10,与该海域1985年及2000年的研究结果相比,长度谱斜率显著降低、截距显著增加,这与小型个体种类占优势密切相关。与历史资料相比,黄海山东海域鱼类群落多样性下降,小型个体比例上升,资源呈衰退趋势。     

Results of satellite tagging of Atlantic bluefin tuna, <Emphasis Type="Italic">Thunnus thynnus</Emphasis>, off the coast of Ireland

Pop-up satellite archival tags were attached to six Atlantic bluefin tuna (Thunnus thynnus) off the west coast of Ireland in autumn 2003 and 2004. The satellite tags measured pressure, ambient temperature and light for the term of deployment. Radio pop-up satellite endpoint positions, light and sea surface temperature estimations of geolocation indicate that two fish tagged minutes apart off the coast of County Donegal, migrated to the eastern and western Atlantic Ocean over the following 8 months. The two fish were 5218 km apart at the termination of the experiment. After tagging in September and popping up the following March and April, one fish had traveled to the western Atlantic while the other was located in the waters off the southwest coast of Portugal. A third fish tagged off the coast of County Donegal in October 2004 moved into the Mediterranean Sea and was caught by a fishing vessel southeast of Malta on 11 June 2005. The results link bluefin tuna feeding on European foraging grounds with known eastern breeding regions and western Atlantic waters.     

SPRING MIGRATION OF EIDERS SOMATERZA MOLLISSIMA IN SOUTHERN SCANDINAVIA

Eider migration in southern Scandinavia in spring 1972 was studied simultaneously at three radar stations and ten field observation sites. The Eiders winter in Danish and West German waters, from which they set out on spring migration on courses ranging from SE to NE; those from the northern part of the wintering area flew SE, those from the south NE, while birds wintering in between these geographical extremes set out on intermediate courses around E. Radar showed that most Eiders fly over the island of Zealand and the peninsula of Skåne, but only exceptionally further north over Sweden. Few Eiders crossing land were registered by field observers and most evidently passed at high altitudes beyond the range of vision. After having crossed Skåne, on varying tracks both south and north of east, the Eiders descended and changed flight direction towards NE. Some Eiders from the northern part of the wintering area circumnavigated Skåne, passing south along the Swedish coast of the Sound, crossing the very narrow peninsula of Falsterbo, and subsequently following the south coast of Skåne eastwards. Eiders from southern Denmark and Germany were often deflected eastwards along the south coast. After having passed Skåne no significant land crossings were made. Upon reaching the province of Blekinge on a course towards NE, the Eiders were deflected E to ESE along the coast and later NNE along the west coast of Öland through Kalmar sound. Approximately 350 000 ducks migrated during daytime of the study period, 250 000 crossing the land of Skåne while 100 000 passed along the south coast. Almost 300 000 migrated north in Kalmar sound, and 17 % of all Eiders passed east of Gland over the open sea. Three distinct peaks of activity during the day were noted in Skåne. The first, at around sunrise, originated from birds resting in waters off Skåne. The second occurred about four hours later and probably consisted of birds which had departed from the wintering area in the early morning. A final peak at sunset was often recorded. Migration also took place during the night, but involved only one fifth of the total number. From combined radar and field counts the total Baltic Eider population is estimated to have been 700 000–800 000 in spring 1972, indicating about 300 000 breeding pairs in the Baltic Sea.     

THE MIGRATION OF PASSERINE NIGHT MIGRANTS ACROSS THE ENGLISH CHANNEL STUDIED BY RADAR

An account is given of the migration of British summer resident small passerine night migrants across the English Channel in spring and autumn, as detected by radar.
The main times of passage of each species have been determined from the trapping records of Dungeness Bird Observatory.
The tracks of the migrants are consistent with the view that they always head about NNW in spring and SSE in autumn but may be drifted by a cross-wind.
The wind-direction and speed had a paramount influence on the volume of migration in both spring and autumn. Temperature had no effect in autumn, and though there was more migration with warmer than cold weather in spring, this need not have been due to the influence of temperature as such.
Small reversed movements occurred, with southerly winds in autumn or, more doubtfully, with northerly winds in spring.     

RADAR TRACKS OF PALAEARCTIC WADERS DEPARTING FROM THE COAST OF GHANA IN SPRING

During the northern spring of 1970 and 1971, wader departures were tracked by radar from saltpans on the coast of Ghana near Accra. All but one of the departures headed northeast, and none were directed along the coast. There was a statistically significant difference between the mean heading of April departures (28°± 10°), and May and June departures (41°± 14°). Projected on great circles, all headings were directed towards the known breeding ranges of the wader species wintering at the saltpans.
In ten species, the dates of the first returning birds to the saltpans in 1966, 1968 and 1970 were about three weeks earlier than dates recorded in Senegal. It is likely that those reaching Senegal follow a coastal route, whereas waders wintering at the coast of Ghana and eastwards to Nigeria evidently make a crossing of the Sahara both in autumn and spring.     

Geolocator tagging reveals Pacific migration of Red‐necked Phalarope Phalaropus lobatus breeding in Scotland

The migration route of Red‐necked Phalarope populations breeding on North Atlantic islands has been subject to considerable speculation. Geolocator tags were fitted to nine Red‐necked Phalaropes breeding in northern Scotland to assess whether they migrated to Palaearctic or Nearctic wintering grounds. Of four birds known to return, two had retained their tags, of which one was recaptured. This male Phalarope left Shetland on 1 August 2012 and crossed the Atlantic Ocean to the Labrador Sea off eastern Canada in 6 days, then moved south to reach Florida during September, crossed the Gulf of Mexico into the Pacific Ocean and reached an area between the Galapagos Islands and the South American coast by mid‐October, where it remained until the end of April, returning by a similar route until the tag battery failed as the bird was crossing the Atlantic Ocean. The total migration of 22 000 km is approximately 60% longer than the previously assumed route to the western part of the Arabian Sea, and this first evidence of migration of a European breeding bird to the Pacific Ocean also helps to indicate the possible migratory route of the large autumn movements of Red‐necked Phalaropes down the east coast of North America.     

大兴安岭地区紫貂的活动节律

借助无线电遥测技术,对４只紫貂全年的活动节律进行了研究,结果表明,紫貂的活动节律春季和冬季的高峰是在晨昏二个阶段,夏秋二季的活动高峰在白昼。春季总体活动节律与夏季相比有明显差异（Ｆ＝４．４９９,ｄｆ＝１,２２,２３;Ｐ＝０．０４５）,春季与秋季的活动节律也有差异（Ｆ＝７．０３９;ｄｆ＝１,２２,２３;Ｐ＝０．０１５）。其总体平均活动强度,春季活动量最小（１７．５３％）,夏季最高（３８．２９％）,其     

Habitat use and movement patterns of bull sharks Carcharhinus leucas determined using pop‐up satellite archival tags

Habitat use, movement and residency of bull sharks Carcharhinus leucas were determined using satellite pop‐up archival transmitting (PAT) tags throughout coastal areas in the U.S., Gulf of Mexico and waters off the south‐east U.S. From 2005 to 2007, 18 fish (mean size = 164 cm fork length, L_F) were tagged over all seasons. Fish retained tags for up to 85 days (median = 30 days). Based on geolocation data from initial tagging location to pop‐off location, C. leucas generally travelled c. 5–6 km day^?1 and travelled an average of 143·6 km. Overall, mean proportions of time at depth revealed C. leucas spent the majority of their time in waters <20 m. They exhibited significant differences among depths but were not found at a particular depth regardless of diurnal period. Most fish occupied temperatures c. 32° C with individuals found mostly between 26 and 33° C. Geolocation data for C. leucas were generally poor and varied considerably but tracks for two individuals revealed long distance movements. One fish travelled from the south‐east coast of the U.S. to coastal Texas near Galveston while another moved up the east coast of the U.S. to South Carolina. Data on C. leucas movements indicated that they are found primarily in shallower waters and tend to remain in the same location over long periods. While some individuals made large‐scale movements over open ocean areas, the results emphasize the importance of the coastal zone for this species as potential essential habitat, particularly in areas of high freshwater inflow.     

Observations on the effect of visual and olfactory ablation on the swimming behavior of migrating adult chum salmon,Oncorhynchus keta

The behavior of chum slamon,Oncorhynchus keta, was studied using ultrasonic telemetry in the waters off the Okhotsk coast of Hokkaido from 1979 to 1981. Thirty-six adult fish were outfitted with a 50 KHz ultrasonic transmitter provided with either a depth sensor, depth/illumination sensors, or depth/ temperature sensors. Twenty-one of the experimental fish were used as controls and left intact. Of the remaining fish, six had their sight destroyed, seven had their olfactory nerves severed or their nares filled with wax, one had both senses destroyed, and one had a sham operation, but had only a shallow transverse cut made in the skin over the olfactory nerves. Control fish and the fish with the sham operation initially swam in a horizontal zigzag pattern while fish with an obliterated sense swam in a similar pattern but to a reduced extent. The horizontal and vertical speeds of the intact fish were faster than those of the fish with a destroyed sense. Amplitude of vertical movements of the intact fish stretched from surface to bottom, while fish with destroyed vision tended towards midwater. Fish without an olfactory sense tended to be at the surface or near the bottom. Regular vertical movement would be effective in refreshing olfactory epithelia which might become acclimated when exposed to one odor. The vertical movements can be found in the horizontal zigzag movements in coastal and near shore migrations, as well as in the stream phase of homing. The zigzag movements, both horizontal and vertical, allow the fish to sense the water masses and locate the correct tributary.     

Seasonal distribution of juvenile Atlantic cod in the southern Gulf of St Lawrence

Seasonal changes in the geographic distribution of juvenile (ages 1–4) Atlantic cod Gadus morhua were determined from research surveys conducted in the southern Gulf of St Lawrence during 1986–87, 1990–91, and 1994. From late June to early October, juvenile cod were most abundant in shallow water (<50 m deep). By early November, all age groups (adults and juveniles) had migrated to deep (>100 m) offshore waters for the winter. For most juveniles, this represented a minimum migration of >225 km (each way). Age 3 and 4 cod migrated greater distances than age 1 and 2 fish. Some age 3 and 4 cod migrated as far as 650 km from their summer and early autumn areas. Although there was partial geographic segregation of juvenile and adult fish during summer and winter, all age groups were found together during the migration. No cod were present in the shallow waters (<80 m deep) of the south-western Gulf during April due, in part, to later than average ice-melt. Large numbers of all age-classes were present in most of the south-eastern Gulf by mid-May.     

Rotifer distributions in the coastal waters of the northeast Pacific Ocean

Absolute abundance of rotifers was assessed from 5 to 80 km across the continental shelf off of the southern Oregon coast (U.S.A.) in the northeast Pacific Ocean. A total of 97 vertically stratified water samples were collected at 49 stations from two depths, 3 and 30 m. Coastal upwelling conditions were indicated, with decreased temperature, increased salinity and higher chlorophyll-a concentrations closer to shore. Two rotifer genera, Synchaeta and Trichocercaoccurred within 16 km of shore with densities increasing closer to shore. Synchaeta reached densities of 64 inds l^–1 while Trichocerca was sparse (<1 inds. l^–1). Rotifers were most abundant at 3 m and the densest aggregations appear to be associated with estuary outlets, suggesting that estuaries may be important in exporting rotifers to nearshore coastal waters.     

青岛近岸水域春、秋季鱼类群落结构

根据2004年春、秋季渔业资源底拖网调查数据,应用单元和多元统计方法分析了青岛近岸水域春、秋季鱼类群落结构。春、秋季调查分别渔获31、32种鱼类,平均每网渔获量分别为7.36kg/h和2.99kg/h,优势种类主要包括赤鼻棱鳀Thrissa chefuensis、大泷六线鱼Hexagrammo sotakii、方氏云鳚Enedrias fangi、黄鳍刺鰕虎鱼Acanthogobius flavimanus、细纹狮子鱼Liparis tanakai和长条蛇鲻Saurida elongata等。聚类分析表明,春、秋季青岛近岸水域鱼类群落都可划分为3个站位组,分别对应于北部、中部和南部调查水域。不同站位组的优势种组成变化较大,不同站位组间种类组成差异显著。分析了造成站位组内种类组成相似的特征种和造成不同站位组间相异的分歧种。不同站位组的特征种不同。赤鼻棱鳀、大泷六线鱼、黄鳍刺鰕虎鱼、方氏云鳚、星康吉鳗Conger myriaster、角木叶鲽Pleuronichthys cornutus和细纹狮子鱼是春季所有站位组间的分歧种;赤鼻棱鳀、白姑鱼Argyrosomus argentatus、大泷六线鱼、带鱼Trichiurus lepturus、短吻红舌鳎Cynoglossus joyneri、方氏云鳚、细条天竺鱼Apogonichthys lineatus、小黄鱼Pseudosciaena polyactis和矛尾鰕虎鱼Chaeturichthys stigmatias是秋季所有站位组间的分歧种。大多数特征种也是不同站位组间的分歧种,主要是由于这些种类的数量分布的空间变化造成的。青岛沿海鱼类群落结构存在明显的时空异质性。     

First geolocator tracks of Swedish red‐necked phalaropes reveal the Scandinavia‐Arabian Sea connection

We studied migration and wintering patterns of a wader with a pelagic lifestyle during the non‐breeding period, the red‐necked phalarope Phalaropus lobatus. Using light‐level geolocation, we obtained three full annual tracks and one autumn migration track of male red‐necked phalaropes caught during breeding in Scandinavia. These tracks confirmed expectations that individuals from the Scandinavian population winter in the Arabian Sea. Migration was accomplished in two to four migration leaps, staging for a few days in the Gulf of Finland (autumn) or the southern Baltic Sea (spring) and for up to a month in or near the Black and Caspian Sea (autumn and spring). In addition, travel speeds suggested that only the flights between the Baltic and Black/Caspian Sea are non‐stop, and thus the birds seem to make additional short stops during the other flights. Stopover time in the Black/Caspian Sea is only 8–10 d in spring but up to 36 d in autumn, which is longer than expected if only used for pre‐migratory fattening to cover the ca 2000 km to the Gulf of Oman. After entering the Arabian Sea via the Gulf of Oman, birds dispersed over the entire presumed winter range. Winter movements appear to correspond to the spatio‐temporal patterns in primary production linked to seasonally changing monsoon winds. These are not only the first tracks of Scandinavian red‐necked phalaropes, but also the first seabird tracks in the Arabian Sea, one of the most productive and dynamic marine areas on the planet.