A short note on the horizontal and vertical movements of a whale shark, Rhincodon typus, tracked by satellite telemetry in the South China Sea

Whale sharks, a global migratory species, are often reported entangled in fishing nets in coastal areas of China. The effectiveness of conservation measures has been constrained by very limited knowledge on their movements and preferred habitats in the coastal areas of China. For the first time, we tracked the movements of 2 whale sharks by satellite telemetry in Mainland China. The tracking results of 1 whale shark revealed that it travelled in the South China Sea in a south-eastern direction, parallel to the eastern coast of Vietnam. Total distance travelled was 1018 km, in approximately 74 days, with a mean speed of 14 km per day. It appeared to head towards the cool upwelling zones in southern Vietnam at the time of the tag's detachment. In our study, it was observed that this whale shark was a surface dweller and spent approximately 45% of its time above 10 m water depth and 90% of its time above 50 m depth. It also tended to stay in water temperatures between 27 and 30 °C, and was rarely recorded in water below 20 °C. This preliminary study indicates the importance of shallow waters as the foraging habitat for whale sharks, and has implications for their management and conservation.     

Sampling efficiency for species composition assessments using the wheel-point method in a semi-arid savanna

A pilot survey to determine the sampling efficiency of the wheel-point method, using the nearest plant method, to assess species composition (using replicate similarity related to sampling intensity, and total sampling time) was conducted on three plot sizes (20 × 20m, 30 × 30m, 40 × 40m) at two sites in a semi-arid savanna. Total sampling time included the time to demarcate a plot. A 40 × 40m plot had the highest precision and repeatability (number of point observations required to achieve a stated asymptotic value), and was followed by a 20 × 20m plot. These relationships were consistent across sites. A 40 × 40m plot recorded the highest sampling times due to the time required to demarcate a plot. A 20 × 20m plot was the most efficient. A model to assist in making decisions regarding a suitable plot and sample size, and for planning and budgeting of vegetation monitoring programs was developed. Future surveys should include a Monte-Carlo data simulation as an adjunct to data collection.     

Composition and seasonal variability of the suprabenthic reef-fish assemblage in False Bay,South Africa

The composition and seasonal variability of a False Bay suprabenthic reef-fish assemblage was investigated monthly at a protected reef site (to a depth of 25 m) for 14 months. In total, 25 484 fish from 28 species (26 demersal) were counted. Sparids dominated the assemblage (50 % of species and 87.3 % of individuals), followed by cheilodactylids (15.4 % of species and 7.5 % of individuals). Pachymetopon blochii (30.6 %), Sarpa salpa (17.7 %), Boopsoidea inornata (16.1 %), Chrysoblephus laticeps (10.4 %) and Spondyliosoma emarginatum (9.2 %) were the five most abundant species, while the ten most abundant species made up over 93 % of censused individuals. Composition was relatively stable year round, irrespective of water temperature variations, with 16 of the 26 reef-fish species censused encountered during more than 10 monthly censuses. Triakus megalopterus and large Chrysoblephus gibbiceps were the only species whose abundance appeared to vary seasonally.     

Distribution and reproduction of the reef fish Petrus rupestris (Pisces: Sparidae) off the coast of South Africa

The red steenbras (Petrus rupestris) is endemic to the south and south-east coasts of South Africa and is the largest member of the family Sparidae. Morphometric relationships between length and mass are given for whole and eviscerated fish. The size distribution of P. rupestris is related to locality and water depth. Juveniles and sub-adults are common in shallow (< 50 m) Cape waters between False Bay and East London. Adults are more common offshore, in deep waters (> 50 m), especially off the coast between East London and Coffee Bay, throughout the year. P. rupestris were found to be rudimentary hermaphrodites. The development of the functional sexes, and the occurrence of sexual dichromatism, are described. Sexual maturity is attained at about 575 mm fork length in those fishes in the spawning areas. Reproductively ripe fishes were taken from Transkei, East London and a small collection was made from the Agulhas Bank. Peak spawning is between August and October. Current management regulations are discussed and advantages of large marine reserves in conservation of this mobile apex predator are outlined.     

Macroanatomic,light and scanning electron microscopic structure of the pecten oculi in northern bald ibis (Geronticus eremita)

Eyes are the most primarily required sensory organs during the migration of migratory birds and Northern Bald Ibises (Geronticus eremita) are known to make long migrations. This study examined for the first time the structure of pecten oculi in northern bald ibises by using macroscopic anatomy as well as light and electron microscopic methods. In the study 20 eye globes from 10 adult bald ibises were used. The pecten was of pleated type. As in most bird species, it was located on the optic nerve head and projects into the vitreous from the optic nerve head. The wider basal part was observed to attached to retina and its free apical part was found in camera vitrea bulbi embedded in corpus vitreum. The pecten had 13–14 accordion like pleats lying between the basal and apical parts. In addition to arterial and venous vessels, numerous capillary vessels as well as melanocytes were observed within each pleat. The bridge binding the pleats at the apical part showed a stronger pigmentation compared to other parts of the pecten. The results of the study indicated that the general morphology of pecten oculi in northern bald ibises which is a migratory bird species were similar to that in other diurnal bird species.     

Movements of deep-sea red crab (Geryon maritae) off South West Africa/Namibia

Of 10 246 red crabs tagged between 1979 and 1984 on the continental slope of Namibia, a total of 1 604 were recaptured by commercial fishermen. Three tagging methods were tested. The most effective method was by inserting the tag through the epimeral suture. Though tagged crabs were released over a range of depths (from 400 to 900 m), the distances that they covered while at large were found to be unrelated to the depth at which they were released. No significant differences were found for distances moved by males compared to immature females, but differences (P< 0,01) did indicate that large males (≥105 mm carapace width (CW)) move farther than small males. Mature females moved significantly farther (P< 0,001) than the other crabs and over 32% moved > 100 km. The farthest distance covered by a single crab was 380 km. No seasonal trends regarding distances or direction moved were noted for either sex or size groupings examined. Mature females did show a tendency, although unrelated to season, to move northwards. Movements of crabs by depth suggested that, although crabs of all sizes and sexes move freely between depths, small males (< 100 mm CW) do tend to favour deeper water than larger males and vice versa. Female crabs tend to favour shallow depths and, of those tagged at 800 and 900 m, over 60% were recaptured shallower than 700 m. Based on the results of this study, it is considered that the movement patterns of G. maritae could best be described as nomadic. A possible reason for the fact that mature females display different movement patterns compared to other crabs in the population is discussed, as are possible implications to the fishery of crab movements between Namibia and Angola     

Cabora Bassa Fish Populations Before and During the First Filling Phase

Pre-impoundment surveys were made in 1973-4. The regulatory effect of continual water discharge from Kariba resulted in extensive dry-season aquatic, rooted, vegetal growth and a comparatively high small-fish population. Of a maximum of 38 species found one, Sarotherodon andersoni, was a new Middle Zambezi record. Lotic and shallow-water species were abundant; gill-nets showed moderately high catches per unit effort. In early November 1974 two-month-old Hydrocymis vittatus juveniles were present indicating an abnormal spawning time. Post-impoundment data from closure on 5 December 1974, to mid-August 1975 are given. The dam filled extremely rapidly to within 10 m of retention level but was thereafter drawn down by heavy floodgate discharge, resulting in continuous slow water-flow and the absence of any stratification or explosive plankton reproduction. Small lotic species, previously abundant, immediately disappeared or became scarce. There was a very high survival of new-spawned young of many migratory species. Growth rates, and abnormal feeding habits caused by post-impoundment stresses, of some of these are described. There was relatively poor reproduction of cichlid species. Soon after closure the first year-class predominated over all other age-groups; these juveniles, and small adult species, concentrated under mats of Elchhomia crassipes. One further species new to the area, Haplochromis carlottae, is recorded.     

Distribution of Euphausiid Crustaceans from the Agulhas Current

Twenty-nine euphausiid species were collected during the three cruises of the S.A.S. Natal in 1958. Of these only Stylocheiron microphthalmia had not previously been taken in South African waters. The commonest euphausiid represented in the collection is a larval series which is provisionally linked with Euphausia recurva or E. mutica. The vertical and horizontal distribution of each species is re-corded and seasonal and latitudinal variation discussed. Stylocheiron suhmii, S. microphthalma and Thysanopoda tricuspidata are proposed as indicators of Agulhas Current water and Nyctiphanes capensis and Euphausia lucens as indicators of water not of Agulhas Current origin. The largest number of euphausiids was found off Port Elizabeth during both summer and winter.     

Euryhaline zooplankton of the Sundays estuary and notes on trophic relationships

The euryhaline component of the Zooplankton in the Sundays River estuary was sampled monthly at 10 stations from August 1979 to April 1981. In deeper regions surface and near-bottom samples were taken (Stations 1-7) using WP2 nets. Shallow (< 2,0 m) stations were sampled in surface waters only. Water temperature ranged between 14-27 °C. A full salinity gradient was present and salinity stratification was well developed. Acartia longipatella was most abundant during winter and spring (maximum 73 300 m^-3) in the lower estuary. The interaction of temperature and salinity as factors regulating temporal and spatial distribution was evident, these factors also interacting in the water column owing to stratification. The pioneer copepod species, seudodiaptomus hessei, attained high abundance following floods or increased river inflow. Three species of mysid shrimps were common in the plankton in summer, each species showing clear zones of maximum distribution. Zooplankton standing stock (dry mass) ranged from < 10 mg m^-3 to 1 450 mg m^-3 In surface samples and < 10 mg m ^-3 to 8 275 mg m ^-3 in bottom samples. Contribution of mysids to standing stock was rarely less than 70% and often exceeded 90%. Differences in standing stock between surface and bottom samples were owing to behavioural differences between the Zooplankton species, particularly the mysids. Behavioural adaptations play an important role in the retention of the indigenous Zooplankton in the estuary. Aspects of trophic relationships are discussed and demonstrate the significance of the Zooplankton in the transfer of energy to higher trophic levels In this estuary.     

Lingering Effects of the 1987 Mass Bleaching of Puerto Rican Coral Reefs in Mid to Late 1988

Abstract

Puerto Rican coral reefs were surveyed with photo-transects and remotely operated vehicle observations, and permanently tagged individual corals were monitored. Seven of eight photo-transects examined between April and October 1988 had bleached or pale colonies of eight species of corals. Between 2.7 and 19% of the living coral surface area was affected on a transect. These observations indicate that additional bleaching occurred after the recovery of most photosymbiotic hosts in January 1988. This continued bleaching may represent the longest bleaching event ever recorded. Individual coral colonies that were bleached in October 1987 were permanently tagged and photo-documented in the field. Recovery of some of these colonies took more than 5 months. Some previously living parts of these colonies died and were overgrown by algae by January 1988. Surveys by remotely operated vehicle during 10–13 February 1988 disclosed bleached colonies of Agaricia spp. toa depth of 60 m and unbleached colonies to a depth of 89 m.     

Pelagic eggs of marine fishes from Park Rynie,KwaZulu-Natal,South Africa: seasonal spawning patterns of the three most common species

For the period 1987 to 1998, pelagic eggs of marine fishes were collected from shelf waters at Park Rynie on the KwaZulu-Natal south coast. The three most numerous eggs collected were those of the mackerel Scomber japonicus,the sardine Sardinops sagax and the East coast roundherring Etrumeus teres. Together they comprised 67 % of all eggs collected. At times single-species egg densities were high, the highest accurately recorded was 850 eggs/cubic metre for S. sagax. All three species were predominantly winter to spring spawners. Theseasonal pattern of sardine eggs at Park Rynie suggests that after entering KwaZulu-Natal waters in June, sardines remain until November or December of each year before returning south to eastern Cape waters. Spawning in the East coast roundherring began in June, peaked in October to November, and tailed off in January. The mackerel showed a similar pattern of spawning, beginning in June and ending in December.     

Pharmacokinetics of oral transmucosal and intramuscular dexmedetomidine combined with buprenorphine in cats

Plasma concentrations and pharmacokinetics of dexmedetomidine and buprenorphine after oral transmucosal (OTM) and intramuscular (i.m.) administration of their combination in healthy adult cats were compared. According to a crossover protocol (1‐month washout), a combination of dexmedetomidine (40 μg/kg) and buprenorphine (20 μg/kg) was given OTM (buccal cavity) or i.m. (quadriceps muscle) in six female neutered cats. Plasma samples were collected through a jugular catheter during a 24‐h period. Plasma dexmedetomidine and buprenorphine concentrations were determined by liquid chromatography–tandem mass spectrometry. Plasma concentration–time data were fitted to compartmental models. For dexmedetomidine and buprenorphine, the area under the plasma concentration–time curve (AUC) and the maximum plasma concentrations (C_max) were significantly lower following OTM than following i.m. administration. For buprenorphine, time to reach C_max was also significantly longer after OTM administration than after i.m. injection. Data suggested that dexmedetomidine (40 μg/kg) combined with buprenorphine (20 μg/kg) is not as well absorbed from the buccal mucosa site as from the intramuscular injection site.     

Diet of the cyprinid fish Barbus aeneus (Burchell) in the P.K. le Roux Dam,South Africa,with special reference to the effect of turbidity on zooplanktivory

Barbus aeneus is one of the most important fishes in the P.K. le Roux Dam, being found over the whole surface and on the bottom down to the thermocline or to 30 m. It is omnivorous, but its diet varies with size. Below a length of 100 mm it feeds mainly on zoobenthos, from 101-300 mm zooplankton is the principal food but in larger fish vegetable food becomes increasingly important. B. aeneus is the principal vertebrate consumer of zooplankton in the dam, but takes only the larger species which are located visually. The quantity of zooplankton in the diet was related, not to its density, but to light and transparency which were the most important non-seasonal influences on the diet. Seasonal effects were marked, zooplankton being most important during summer and autumn while empty stomachs were most frequent in winter and spring. In rivers, larger B. aeneus feed on bigger invertebrates and on vegetable material. These are limited in the P.K. le Roux Dam and sub-adults experience high mortality once they can no longer feed efficiently on zooplankton. The size at which this occurs is determined largely by turbidity, and this should be taken into consideration in formulating management policies.     

Observations on the Movement Patterns and Daily Home Range Size of Impala,Aepyceros Melampus (Lichtenstein) in the Kruger National Park

The movements and other behavioural and physiological patterns of impala and of some of the other more abundant game species in the Kruger National Park were studied to provide information which could be applied to their management, especially in regard to the artificial provision of water.

Preliminary results reveal that the daily home ranges of impala are relatively small (±0,98 km²/24 h), their short daily movements (±3,0 km/24 h) are especially restricted at night (±0,6 km/12 h) and that surface water and the availability of edible succulent vegetation in the vicinity thereof, strongly influence the regional distribution of this species in the Kruger National Park. Maps are included to illustrate typical impala movements in relation to the distribution of watering points and other ecological features, while quantitative information on their movements and daily home range size is compared with that of blue wildebeest, Connochaefes taurinus (Burchell), Burchell's zebra, Equus burchellii antiquorum H. Smith, buffalo, Syncerus caffer (Span-man) and the elephant, Loxodonta africana (Blumenbach).     

Homozygosity of single nucleotide polymorphisms in the 3′ region of the canine estrogen receptor 1 gene is greater in Toy Poodles than in Miniature Dachshunds and Chihuahuas

Differences in the distribution of single nucleotide polymorphisms (SNPs) and haplotypes in the estrogen receptor α gene (ESR1) were examined in Miniature Dachshunds (n = 48), Chihuahuas (n = 20) and Toy Poodles (n = 18). Five DNA fragments located in the 40‐kb region at the 3′ end of ESR1 were amplified by polymerase chain reaction and were directly sequenced. We compared allele, genotype and estimated haplotype frequencies at each SNP in the 3′ end of ESR1 for these three breeds of small dog. The frequency of the major allele and the genotype frequency of the major allele homozygotes, were significantly higher in Toy Poodles for five SNPs (SNP #5, #14–17) than in Miniature Dachshunds, and significantly higher in Toy Poodles than Chihuahuas for three SNPs (SNP #15–17). A common haplotype block was identified in an approximately 20‐kb region encompassing four SNPs (SNPs # 14–17). The frequencies of the most abundant estimated haplotype (GTTG) and GTTG homozygotes were significantly higher in Toy Poodles than in the other two breeds. These results imply that homozygosity for the allele, genotype and haplotype distribution within the block at the 3′ end of ESR1 is greater in Toy Poodles than in Miniature Dachshunds and Chihuahuas.     

黄土高原不同草地类型对水稳性团聚体粒径分布及稳定性的影响

本研究在甘肃兰州选择了4种不同类型的人工草地与天然草地为研究对象,分别为苜蓿草地、冰草草地、柠条灌木草地及针茅草地,其中针茅草地为天然草地。分析了4种草地类型0~40 cm土层的土壤水稳性团聚体粒径分布特征、平均重量直径(mean weight diameter, MWD)以及它们之间的差异性和相关性。结果表明,>2 mm和<0.25 mm粒径的水稳性团聚体为优势粒径;在土壤表层0~20 cm,针茅草地>0.25 mm粒径的水稳性团聚体显著高于其他草地类型(P<0.05),而在20~40 cm土层,苜蓿草地最高,说明在表层针茅草地对土壤结构的改良最优,随土层加深苜蓿草地对土壤结构的改良效果突出;苜蓿草地MWD值由表层0~10 cm的1.04 mm降低到30~40 cm的0.72 mm,下降了31%,而其他草地类型下降了50%~80%,说明苜蓿草地对不同层次土壤结构改良效果的差异性最小。MWD值与>0.25 mm粒径的水稳性团聚体含量和有机质呈极显著的正相关关系,与土壤容重呈极显著的负相关关系,表明水稳性大团聚体和有机质含量的增加可有效促进土壤结构的改良,加强土壤结构的稳定性,提高土壤的抗侵蚀能力。     

湖南屏风界候鸟种类与迁徙规律调查

2001-2006年，通过对湖南省屏风界候鸟种类及迁徙规律的调查，表明屏风界候乌资源较为丰富，共环志鸟类26科95种，其中国家Ⅱ级保护鸟类18种。同时摸清了该地区候乌迁徙的主要规律，对候鸟迁徙通道的形成原因进行了分析，为该地区鸟类资源的有效保护和管理提供了科学依据。     

New Zealand’s Cetaceans and Pinnipeds

The 8 species of baleen whale in New Zealand waters range in length from 6 to 30+ metres, and the 25 species of toothed whale range up to 18 metres. A single porpoise species is known in New Zealand sub-Antarctic waters.

The baleen whales and many of the toothed whales are migratory, and New Zealand straddles their well-defined routes: a combination which allowed whaling to flourish. The toothed whales are the more gregarious and may indulge in mass strandings. Current research aims to investigate the biology of all of the whale species.

The otariid, or eared seals found in the New Zealand region are the New Zealand sealion and the New Zealand fur seal. The commonest of the phocid, or earless seals on the New Zealand coast are the elephant and leopard seals. All of these breed in the southern parts of the region but range further north. The fur seal population is rising slowly, but the small population size of the New Zealand sealion gives cause for concern.

Marine mammals form an important part of the fauna of the New Zealand region, and veterinary knowledge and general research should be increased.