Showing papers on "Heron published in 1990"

Comparison of polychlorinated dibenzodioxin levels with hepatic mixed-function oxidase induction in great blue herons.

Abstract: As part of the Canadian Wildlife Service monitoring of great blue herons in British Columbia, eggs were collected from three colonies with low, intermediate, and high levels of PCDD and PCDF contamination: Nicomekl, Vancouver, and Crofton, respectively. One egg from each nest was used for chemical analysis by CC‐MS; the others were hatched. Liver microsomes were prepared from the heron chicks and used for determination of cytochrome P‐450‐dependent activities. No erythromycin N‐demethylase activity was found in any sample. Ethoxyresorufin O‐dealkylase activity in the Nicomekl group was similar to that in pigeons, a control altricial species. The ethoxyresorufin activity in the herons from the Crofton colony was 2.6‐fold higher than in the Nicomekl group. The Vancouver colony was intermediate. No difference among the three heron colonies was found in pentoxyresorufin O‐dealkylase activity, although levels were 20–33 times that in the pigeon. Chemical analysis was carried out on paired heron eggs. Vancouver...

Pygidiopsis ardeae n. sp. (Digenea: Heterophyidae: Pygidiopsinae) in the grey heron Ardea cinerea L. from Denmark

Abstract: A new species, Pygidiopsis ardeae (Heterophyidae, Pygidiopsinae), is described, using both light and stereoscan electron microscopy, from the grey heron Ardea cinerea L. (Ardeidae) from Denmark. The species has previously (as P. genata) been recorded in dogs fed on plaice and flounders from Danish waters. It developed experimentally in domestic chickens and pigeons. No species of Pygidiopsis Looss, 1907 has previously been described from birds in northern Europe. P. ardeae is very similar to the type-species, P. genata Looss, 1907, from Egypt, but the two species have different life-cycles. P. ardeae differs from P. piclaumoreli Dollfus & Capron, 1958 from Senegal in its size and the disposition of vitelline follicles. P. plana (Linton, 1928) Price, 1933, from a green heron from the eastern USA, is larger than P. ardeae and has a wide, sac-like prepharynx.

Nearest Neighbour Analysis and Wedge‐Tailed Shearwater Burrow Patterns on Heron and Masthead Islands, Great Barrier Reef

Abstract: Heron and Masthead Islands in the Capricorn Group of the Great Barrier Reef Marine Park support major nesting colonies of the wedge‐tailed shearwater. The distribution pattern of shearwater nesting burrows was established for particular habitats on both islands by means of a nearest neighbour analysis. Areas of Pisonia grandis forest had the highest burrow density and near‐random distribution patterns for burrows while the island fringes had the lowest densities and higher degrees of aggregation. These results may reflect the importance of social communication within a wedge‐tailed shearwater colony. Burrows are distributed in patches around the margins of the colony where clear and fringe habitats are represented, but randomly near the centre in Pisonia areas, where sheer numbers may negate the need for further aggregation. Copyright

Holoplanktonic molluscs (Gastropoda ; Thecosomata, Gymnosomata and Heteropoda) from the waters of Australia and Papua New Guinea : their taxonomy, distribution and biology

Abstract: This study provides the first comprehensive study of the taxonomy, distribution, and biology of pteropod and heteropod molluscs occurring in the waters surrounding Australia and Papua New Guinea. Approximately 1400 samples were examined from 10 regions encompassing the Northwest Shelf, Gulf of Carpentaria, north and southeast coasts of Papua New Guinea, the Great Barrier Reef and the southeast coast of Australia. Field studies were conducted near Lizard Island, in the northern Great Barrier Reef and Heron Island in the southern Great Barrier Reef from 1985 to 1988. Animals were collected from surface waters and examined live in situ and in vitro. The shelled species are documented with the aid of scanning electron microscopy and photomicrographs and illustrations were made of the shell-less species. Forty-seven pteropod species/taxa (Thecosomata and Gymnosomata) were found to occur in Australian and Papua New Guinean waters. Thirty-five of these are recorded here for the first time from the region, or their distributional ranges have been considerably extended (> 1000 km) from those previously reported from the literature. First records from the southwest Pacific Ocean are given for the bathypelagic euthecosomes, Clio andreae (Boas, 1886) and C. scheelei (Munthe, 1888). Juveniles of the euthecosome, Hyalocylis striata (Rang, 1828) are described for the first time, this being the only euthecosome whose juveniles were unknown. Two new species of gymnosomatous pteropods, Pneumodermopsis spoeli nov. sp. and Pneumoderma heronensis nov. sp. are described. Thirty-eight pteropod species were found to be cosmopolitan in distribution occurring in both the waters of the southwest Pacific and southeast Indian Oceans. Seven species were only reported from the southwest Pacific Ocean and one species was found exclusively from the southeast Indian Ocean. The highest species diversity of pteropods was reported from the central Great Barrier Reef and southeast coast of Australia. Twenty-four species of heteropods including veliger stages of the atlantids are documented. Twenty-two species are recorded for the first time from the Australian and Papua New Guinean region or their ranges are considerably extended by more than 1000 km. A trematode digenean parasite is described for the first time from heteropods and the potential role of heteropods as hosts of parasites found in commercially important fish species is discussed. The distribution and biology of the most common Austral ian heteropod, Atlanta gaudichaudi Soule yet, 1852 is investigated in the surface waters offshore from Lizard and Heron Islands. Over 70 % of animals were in veliger stage in both summer and winter months. The abundance of this atlantid was significantly different between sampling regions and abundances were highest in winter months at Lizard Island and summer months at Heron Island. The sperm ultrastructure of Atlanta gaudichaudi is examined for discussion of the systematics of the heteropods. The phylogenetic position of heteropods is found to conform to that of the Mesogastropoda, especially the Littorinacea by similarity of sperm, presence of nurse cells in the carinariid heteropods and littorinids, and homology of the male reproductive apparatus. The distribution and seasonal abundance of the holoplanktonic molluscan fauna is examined from the waters of the Great Barrier Reef. Twenty-eight species were collected from surface waters within the Great Barrier Reef and in the waters of the adjacent Coral Sea. Three species, Creseis acicula (Rang, 1828), C. chierchiae (Boas, 1886) and Atlanta gaudichaudi Souleyet, 1852 were found in extremely high abundances, occasionally occurring in blooms. Although the dominant species were similar in both regions, significant differences in the abundance of the most common species were found between Lizard and Heron Islands. These species were generally more abundant in the Trade Wind season at Lizard Island, and in the non-Trade Wind season at Heron Island.