Showing papers on "Heron published in 1998"

Effects of ecotourists on bird behaviour at Loxahatchee National Wildlife Refuge, Florida.

Abstract: Increasingly, natural areas are exposed to people who come to view, study or photograph wildlife. In order to develop appropriate management plans for both avian and human use of natural environments it is essential to understand how people affect foraging birds. The foraging behaviour of five species of water-birds at Loxahatchee (Arthur B. Marshall National Wildlife Refuge), part of the Everglades, in Southern Florida was observed, between 1992 and 1994, from a dike that received many visitors. Species examined included common gallinule (Gallinula chloropus), sora rail (Porzana carolina), glossy ibis (Plegadis falcinellus), little blue heron (Egretta caerulea) and Louisiana heron (E. tricolor). These birds were observed before people were near, while people were present, and following the departure of people. Variation in feeding behaviour was largely explained by whether people were present, the number of people present, and the amount of noise made by the people. For all species, time devoted to feeding and number of strikes or pecks decreased while people were present. The percentage of time spent foraging and the number of strikes decreased as the noise made by people increased. Birds that were closer to the path flew away from people more often than birds that were further away. Birds usually swam or flew away from the path while people were present.

Digenetic trematodes of the genus Clinostomum Leidy, 1856 (Digenea: Clinostomidae) from birds of Queensland, Australia, including C. wilsoni n. sp. from Egretta intermedia

Abstract: Two species of Clinostomum previously described from Australia, C. hornum from Botaurus poiciloptilus (Australian bittern) and Nycticorax caledonicus (Nankeen night heron) and C. australiense from Pelecanus conspicillatus (Australian pelican), which have previously been synonymised with C. complanatum, are redescribed and recognised as valid species. In addition, C. complanatum is recorded from Egretta alba (large egret), E. garzetta (little egret), E. intermedia (plumed egret), N. caledonicus and Ardea novaehollandiae (white-faced heron). C. wilsoni n. sp. is described from E. intermedia from Queensland. C. wilsoni differs from the other three species in size and shape of the body and in the oral collar, oral sucker, intestinal caeca, caecal diverticula and position of testes. Taxonomic problems within the genus Clinostomum are discussed.

Molecular and Osteological Heron Phylogenies: Sources Of Incongruence

Abstract: Payne and Risley's (1976) comparison of 33 osteological characters of herons was the first cladistic estimate of heron phylogeny. Among their findings were two major clades: (1) Boat-billed Heron (Cochlearius cochlearius), night-herons, and bitterns; and (2) ti- ger-herons and day-herons. In contrast, more recent DNA-DNA hybridization comparisons, cladistic analyses of vocalizations, and mtDNA sequence data portray a more asymmetric phylogeny, with day-herons and night-herons forming a clade with bitterns as their sister group, and tiger-herons and the Boat-billed Heron branching basally. To explore the source of the disagreement between these phylogenetic estimates, we reanalyzed the osteological data using modern cladistic methods and compared the results with the DNA-DNA hybrid- ization tree using taxonomic congruence analysis. Character-by-character comparisons be- tween trees and among lineages within trees suggest that similar cranial morphology in the relatively unrelated tiger-herons and day-herons has resulted in the misleading attraction of these two lineages in osteological estimates of phylogeny. Apparent convergence in bill mor- phology and modifications of orbital structures for nocturnal feeding in night-herons and Boat-billed herons have led to further disagreement between data sets. In part, problems in the osteological data stem from the relatively small character matrix of Payne and Risley (1976), but ultimately they may derive from using highly adaptive characters to reconstruct phylogeny. In this case, the cranial characters are functionally correlated as part of the pi- scivorous heron Bauplan. As such, they relate to the forces responsible for speciation and divergence in the early history of the group but may not be useful for phylogenetic inference. The discovery of bias in cranial characters underscores the value of taxonomic congruence analysis and the need to explore cases of phylogenetic incongruence. Received 19 June 1996, accepted 24 June 1997. CONGRUENCE ANALYSIS of independent esti- mates of phylogeny is a useful method for judging phylogenetic accuracy (Mickevich and Johnson 1976). Agreement in branching pat- terns in trees from different data sets provides strong evidence of phylogeny (Bledsoe and Raikow 1990, Swofford 1991, Miyamoto and Fitch 1995). When phylogenies disagree, how- ever, interesting lessons about evolution and the mechanics of phylogenetic estimation also may be learned. Incongruence can result from biased data derived from poor sampling strat- egies (e.g. using correlated characters) or idio- syncrasies of evolution (e.g. differences in rates of character change or character convergence) in one or both data sets (Wiley 1981, Patterson et al. 1993). Because the discovery and expli- cation of characters that have evolved in unusu- al ways are main goals of evolutionary biology, the analysis of incongruence is an interesting

Observations on the diet and feeding habits of the epaulette shark, Hemiscyllium ocellatum (Bonnaterre), on Heron Island Reef, Great Barrier Reef, Australia

Abstract: The diet and feeding habits of the epaulette shark, Hemiscyllium ocellatum, were investigated through stomach content analysis. Five groups of prey items were found. The index of relative importance showed worms and crabs to be of greatest value at 51.3% and 40.1% respectively. The three minor prey groups were shrimps (7.7%), small fishes (0.7%) and amphipods (0.3%). Epaulette sharks tend to be crepuscular, although feeding bouts may occur at any time. They appear to be opportunistic predators, using olfaction and electroreception in prey capture. This species appears to be an important benthic predator in the reef flat environment on Heron Island Reef.

Morphology and Toxicology of Prorocentrum faustiae sp. nov., a Toxic Species of Non-Planktonic Dinoflagellate from Heron Island, Australia

Abstract: A new species of non-planktonic dinoflagellate, Prorocentrum faustiae isolated from the Australian Barrier Reef, is described using scanning electron microscopy. This species can be identified by its shape, size, surface micromorphology, architecture of the periflagellar area, and intercalary band. Analysis of cells of Prorocentrum faustiae using the HPLC-fluoroscent method confirms the production of both okadaic acid and DTX-1.

Lepocreadiidae (Digenea) of Australian coastal fishes: new species of Opechona Looss, 1907, Lepotrema Ozaki, 1932 and Bianium Stunkard, 1930 and comments on other species reported for the first time or poorly known in Australian waters

Abstract: Opechona austrobacillaris n. sp. is described from Pomatomus saltatrix from marine sites off Western Australia and New South Wales, Australia. It differs from O. bacillaris in its elongate outline, small ventral sucker, longer pseudoesophagus (relative to the oesophagus), relatively shorter ventral sucker to ovary distance and the relatively longer post-testicular region. Lepotrema monile n. sp. is described from Pomacentrus wardi from Heron Island, Queensland. It differs from its congeners in the sphincter around the distal metraterm and the more-or-less oval ovary. Bianium spongiosum n. sp. is described from Ostracion cubicus from Lizard Island, Queensland. It differs from its congeners in lacking lateral flaps in the forebody, but in having large, internal spongiform patches in the lateral forebody. The following species are redescribed from Australian sites: Lepocreadium oyabitcha from Abudefduf whitleyi, Lizard Island; Clavogalea trachinoti from Trachinotus botla, Heron Island and T. coppingeri, New South Wales, Stradbroke Island, Queensland and Heron Island; Myzoxenus insolens from Notolabrus parilus, Western Australia; Bulbocirrus aulostomi from Aulostomus chinensis, Heron Island; Lepocreadioides orientalis [new synonyms: Bicaudum interruptum Bilqees, 1973; Lepocreadioides interruptum (Bilqees, 1973) Madhavi, Narasimhulu & Shameem, 1986; Lepocreadioides discum Wang, 1986; Lepocreadioides sp. of Karyakarte & Yadav (1976)] from Cynoglossus bilineata, Moreton Bay, Queensland; Hypocreadium patellare from Sufflamen chrysopterus, Heron Island; Echeneidocoelium indicum from Echeneis naucrates, Heron Island; Multitestis pyriformis from Epinephelus cyanopodus, Heron Island; Pseudopisthogonoporus vitellosus from Naso brevirostris, Heron Island; and Bianium hispidum from Torquigener whitleyi and T. pleurogramma, southern Queensland. Only M. solens and M. pyriformis have been reported from Australian waters before; both are new host records.

Key areas for wintering North American herons

Abstract: -Nearly all North American heron populations are migratory, but details of where they winter are little known Locations where North American herons wintwe were identified using banding recovery data North American herons winter from Canada through northern South America but especially in eastern North America south of New York, Florida, California, Louisiana, Texas, Mexico and Cuba, these areas accounting for 63% of winter recoveries We identified regions where recoveries for various species clustered as "key areas" These forty-three areas constitute a network of areas that hold sites that likely are important to wintering North American herons Within each area, we identify specific sites that are potentially important to wintering herons The relative importance of each area and site within the network must be evaluated by further on the ground inventory Because of biases inherent in the available data, these hypothesized key areas are indicative rather than exhaustive As a first cut, this network of areas can serve to inform further inventory activities and can provide an initial basis to begin planning for the year-round conservation of North American heron populations Received 2 April 1996, accepted 14 May 1998

The failure of a scientific critique: David Heron, Karl Pearson and Mendelian eugenics.

Abstract: L'interpretation de Mendel sur l'heredite des maladies mentales est critiquee par David Heron et Karl Pearson

Heron of alexandria

Abstract: This is the first study to deal with Greek mathematics from the viewpoint of cultural history. Mathematics, and especially the teaching of mathematics, did not proceed in isolation, but developed along lines parallel to the development of general literate culture.