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Culum Brown - One of the best experts on this subject based on the ideXlab platform.

  • preliminary observations on the movement ecology of a crested horn shark Heterodontus galeatus
    Journal of Fish Biology, 2021
    Co-Authors: Nathan Charles Bass, Joanna Day, Tristan L Guttridge, Nathan A Knott, Culum Brown
    Abstract:

    The residency and movements of a single acoustically tagged female crested horn shark (Heterodontus galeatus) were monitored in Jervis Bay, Australia. The individual was intermittently detected by receivers throughout the 8-year study period and showed preference for particular rocky reefs in terms of its residency indices and duration of residency events. This individual exhibited lower residency and dissimilar movement patterns to that of the well studied and sympatric Port Jackson shark (Heterodontus portusjacksoni), highlighting the need for research into the basic life history and movement ecology of H. galeatus. This article is protected by copyright. All rights reserved.

  • lack of social preference between unfamiliar and familiar juvenile port jackson sharks Heterodontus portusjacksoni
    Journal of Fish Biology, 2019
    Co-Authors: Catarina Vila Pouca, Culum Brown
    Abstract:

    This study investigated whether captive-reared juvenile Port Jackson sharks Heterodontus portusjacksoni choose to aggregate and if familiarity is one of the mechanisms driving social preference. In a controlled binary-choice experiment, juvenile sharks were given the option to associate or not with unfamiliar conspecifics, or to associate or not with familiar conspecifics. In neither group did juvenile H. portusjacksoni actively choose to associate with conspecifics, but familiarity decreased the proportion of time spent near a conspecific only during the initial phase of the experiment. Treatment (1 or 3 shoal mates), sex and size had no effect on aggregation behaviour. These findings suggest that familiarity is not a driver of social preferences in juvenile H. portusjacksoni, contrary to results in another shark species. Additionally, adult H. portusjacksoni form large aggregations during the breeding season and actively associate with familiar sex and size-matched individuals, thus our results suggest the species undergoes an ontogenetic shift in social behaviour.

  • characterization of 12 polymorphic microsatellite loci in the port jackson shark Heterodontus portusjacksoni meyer 1793
    Marine Biodiversity, 2019
    Co-Authors: Jennalee A Clark, Christopher Izzo, Jane E. Williamson, Culum Brown, Michael R Gillings, Michael G Gardner, Joanna Day
    Abstract:

    The Port Jackson Shark (Heterodontus portusjacksoni) is an epibenthic, oviparous species endemic to the southern half of Australia. Understanding the genetic structure, ecology and reproductive behaviours of this species is essential for developing appropriate management and conservation strategies. However, research has been hampered due a lack of suitable genetic markers. Here, we developed 12 microsatellite loci for H. portusjacksoni. The number of alleles at these polymorphic loci ranged from 3 to 22 and the observed heterozygosity ranged from 0.15 to 0.84. Six of twelve loci successfully cross-amplified in the closely related Crested Hornshark, H. galeatus (Gunther, 1870). These markers will aid in studying the spatial and reproductive ecology of H. portusjacksoni and other heterodontid sharks.

  • Individual personality differences in Port Jackson sharks Heterodontus portusjacksoni
    Journal of fish biology, 2016
    Co-Authors: Evan E. Byrnes, Culum Brown
    Abstract:

    This study examined interindividual personality differences between Port Jackson sharks Heterodontus portusjacksoni utilizing a standard boldness assay. Additionally, the correlation between differences in individual boldness and stress reactivity was examined, exploring indications of individual coping styles. Heterodontus portusjacksoni demonstrated highly repeatable individual differences in boldness and stress reactivity. Individual boldness scores were highly repeatable across four trials such that individuals that were the fastest to emerge in the first trial were also the fastest to emerge in subsequent trials. Additionally, individuals that were the most reactive to a handling stressor in the first trial were also the most reactive in a second trial. The strong link between boldness and stress response commonly found in teleosts was also evident in this study, providing evidence of proactive-reactive coping styles in H. portusjacksoni. These results demonstrate the presence of individual personality differences in sharks for the first time. Understanding how personality influences variation in elasmobranch behaviour such as prey choice, habitat use and activity levels is critical to better managing these top predators which play important ecological roles in marine ecosystems.

  • laterality strength is linked to stress reactivity in port jackson sharks Heterodontus portusjacksoni
    Behavioural Brain Research, 2016
    Co-Authors: Evan E. Byrnes, Catarina Vila Pouca, Culum Brown
    Abstract:

    Cerebral lateralization is an evolutionarily deep-rooted trait, ubiquitous among the vertebrates and present even in some invertebrates. Despite the advantages of cerebral lateralization in enhancing cognition and facilitating greater social cohesion, large within population laterality variation exists in many animal species. It is proposed that this variation is maintained due links with inter-individual personality trait differences. Here we explored for lateralization in Port Jackson sharks (Heterodontus portusjacksoni) using T-maze turn and rotational swimming tasks. Additionally, we explored for a link between personality traits, boldness and stress reactivity, and cerebral lateralization. Sharks demonstrated large individual and sex biased laterality variation, with females demonstrating greater lateralization than males overall. Stress reactivity, but not boldness, was found to significantly correlate with lateralization strength. Stronger lateralized individuals were more reactive to stress. Demonstrating laterality in elasmobranchs for the first time indicates ancient evolutionary roots of vertebrate lateralization approximately 240 million years old. Greater lateralization in female elasmobranchs may be related enhancing females' ability to process multiple stimuli during mating, which could increase survivability and facilitate insemination. Despite contrasting evidence in teleost fishes, the results of this study suggest that stress reactivity, and other personality traits, may be linked to variation in lateralization.

Felipe Galvanmagana - One of the best experts on this subject based on the ideXlab platform.

  • feeding habits of the horn shark Heterodontus francisci girard 1855 in the northwest of baja california sur mexico
    Journal of Applied Ichthyology, 2020
    Co-Authors: Christian Cortesfuentes, Felipe Galvanmagana, Maria Del Rosario Simentalanguiano, Marco Antonio Medinalopez
    Abstract:

    The feeding habits of the horn shark, Heterodontus francisci (Girard, 1855), were examined in the area of Bahia Tortugas, Baja California Sur, Mexico in the spring, summer and fall of 2014. A total of 78 stomachs were collected, of which 46 (59%) contained food and 32 (41%) were empty. According to the percent Index of Relative Importance (%IRI), the most important prey categories in H. francisci's diet were anomurans (66%), cephalopods (7.2%), lobsters (4.7%), fishes (4.2%) and sea urchins (2.3%). The main prey were the anomuran Blepharipoda occidentalis (65.2%), the octopus Octopus bimaculatus (5.4%), the lobster Panulirus interruptus (4.7%) and the sea urchin Echinometra vanbrunti (2.6%). According to the Levin standardized Index (Bi), the trophic niche breadth in H. francisci is low (Bᵢ = 0.21), making it a specialist predator. The species was classified as a tertiary consumer (trophic position = 4.06).

  • observations on the feeding habits of the shark Heterodontus francisci girard 1854 chondrichthyes heterodontidae in san ignacio lagoon baja california sur mexico
    Ciencias Marinas, 1997
    Co-Authors: J C Segurazarzosa, L A Abitiacardenas, Felipe Galvanmagana
    Abstract:

    Se revisaron 108 estomagos del tiburon Heterodontus francisci Girard, 1854, capturados en Laguna San Ignacio, Baja California Sur, en muestreos trimestrales de enero de 1992 a febrero de 1993. Esta especie se encuentra en la laguna durante todo el ano, disminuyendo su abundancia durante las estaciones de verano y otono. De acuerdo con el indice de importancia relativa (IIR), el tiburon se alimenta de los siguientes invertebrados bentonicos: gasteropodos (Lucapinella milleri y Calyptraea spp.), crustaceos (Callinectes bellicosus, Penaeus spp. e isopodos), pelecipodos (no identificados), sipunculidos (Sipunculus nudus), cefalopodos (Octopus spp.), asi como de peces pequenos (Syngnathus auliscus). Heterodontus francisci es un consumidor de tercer orden, ya que es una especie bentonica, predominantemente carnivora, que se caracteriza por ser un depredador selectivo de habitos nocturnos y/o crepusculares. A total of 108 stomach contents of horn shark (Heterodontus francisci Girard, 1854) from San Ignacio Lagoon were analyzed. The samples were taken seasonally from January 1992 to February 1993. This species occurred all year round, with low abundance in summer and fall. The index of relative importance (IRI) was used to determine the prey importance. The horn shark feeds mainly on benthic invertebrates, such as gastropods (Lucapinella milleri and Calyptraea spp.), crustaceans (Callinectes bellicosus, Penaeus spp. and isopods), pelecypods (unidentified). sipunculoids (Sipunculus nudus), cephalopods (Octopus spp.), as well as on small fishes (Syngnathus auliscus). This shark is a third-order consumer, because it is a predominantly carnivorous benthic species: it is a selective predator with nocturnal or crepuscular habits.

  • observaciones sobre la alimentacion del tiburon Heterodontus francisci girard 1854 chondrichthyes heterodontidae en laguna san ignacio baja california sur mexico observations on the feeding habits of the shark Heterodontus francisci girard 1854 chondrichthyes heterodontidae in san ignacio lagoon baja california sur mexico
    1996
    Co-Authors: J C Segurazarzosa, Felipe Galvanmagana, Leonardo Andres Abitiacardena, Gomez Palacio
    Abstract:

    A total of 108 stomach contents of horn shark (Heterodontus francisci Girard, 1854) from San Ignacio Lagoon were analyzed. The samples were taken seasonally from January 1992 to February 1993. This species occurred all year round, with low abundance in summer and fall. The index of relative importance (IRI) was used to determine the prey importance. The horn shark feeds mainly on

Shigehiro Kuraku - One of the best experts on this subject based on the ideXlab platform.

  • a de novo transcriptome assembly of the zebra bullhead shark Heterodontus zebra
    Scientific Data, 2018
    Co-Authors: Koh Onimaru, Kaori Tatsumi, Kazuhiro Shibagaki, Shigehiro Kuraku
    Abstract:

    Although cartilaginous fishes have played crucial roles in various fields, including evolutionary biology, marine ecology, bioresources, and aquarium exhibitions, molecular information for these species is poorly available. The present study reports a transcriptome assembly from an embryo of the zebra bullhead shark (Heterodontus zebra), produced by paired-end RNA sequencing. Transcriptome data is generated with a de novo transcriptome assembler, Trinity. Amino acid sequences are predicted from the assemblies, using TransDecoder. Because cartilaginous fishes serve as the outgroup of bony vertebrates, the data would contribute to comparative analyses of a various biological fields. In addition, this study would be useful for conservation biology, such as transcriptome-based population genetics.

  • Transcriptome data of the zebra bullhead shark
    2018
    Co-Authors: Koh Onimaru, Kaori Tatsumi, Kazuhiro Shibagaki, Shigehiro Kuraku
    Abstract:

    Supplementary data of Onimaru et al., "A de novo transcriptome assembly of the zebra bullhead shark, Heterodontus zebra

  • Distances and evolutionary rates for chondrichthyan and tetrapod representatives.
    2013
    Co-Authors: Adina J. Renz, Axel Meyer, Shigehiro Kuraku
    Abstract:

    Distances (number of substitutions per site) were calculated by codeml for different pairs of species using Callorhinchus milii (Cm) as outgroup. Applying divergence times estimated in this study (306 Ma) as well as previous studies (203 Ma, 312 Ma and 330 Ma), evolutionary rates were calculated for three chondrichthyans and four tetrapod species. Abbreviations: aa, amino acid; Ma, million years ago; Hf, Heterodontus francisci; Sc, Scyliorhinus canicula; Le, Leucoraja erinacea; Gg, Gallus gallus; Hs, Homo sapiens; Ac, Anolis carolinensis; Xt, Xenopus tropicalis; O, Last common ancestor of the two selected species.

J C Segurazarzosa - One of the best experts on this subject based on the ideXlab platform.

  • observations on the feeding habits of the shark Heterodontus francisci girard 1854 chondrichthyes heterodontidae in san ignacio lagoon baja california sur mexico
    Ciencias Marinas, 1997
    Co-Authors: J C Segurazarzosa, L A Abitiacardenas, Felipe Galvanmagana
    Abstract:

    Se revisaron 108 estomagos del tiburon Heterodontus francisci Girard, 1854, capturados en Laguna San Ignacio, Baja California Sur, en muestreos trimestrales de enero de 1992 a febrero de 1993. Esta especie se encuentra en la laguna durante todo el ano, disminuyendo su abundancia durante las estaciones de verano y otono. De acuerdo con el indice de importancia relativa (IIR), el tiburon se alimenta de los siguientes invertebrados bentonicos: gasteropodos (Lucapinella milleri y Calyptraea spp.), crustaceos (Callinectes bellicosus, Penaeus spp. e isopodos), pelecipodos (no identificados), sipunculidos (Sipunculus nudus), cefalopodos (Octopus spp.), asi como de peces pequenos (Syngnathus auliscus). Heterodontus francisci es un consumidor de tercer orden, ya que es una especie bentonica, predominantemente carnivora, que se caracteriza por ser un depredador selectivo de habitos nocturnos y/o crepusculares. A total of 108 stomach contents of horn shark (Heterodontus francisci Girard, 1854) from San Ignacio Lagoon were analyzed. The samples were taken seasonally from January 1992 to February 1993. This species occurred all year round, with low abundance in summer and fall. The index of relative importance (IRI) was used to determine the prey importance. The horn shark feeds mainly on benthic invertebrates, such as gastropods (Lucapinella milleri and Calyptraea spp.), crustaceans (Callinectes bellicosus, Penaeus spp. and isopods), pelecypods (unidentified). sipunculoids (Sipunculus nudus), cephalopods (Octopus spp.), as well as on small fishes (Syngnathus auliscus). This shark is a third-order consumer, because it is a predominantly carnivorous benthic species: it is a selective predator with nocturnal or crepuscular habits.

  • observaciones sobre la alimentacion del tiburon Heterodontus francisci girard 1854 chondrichthyes heterodontidae en laguna san ignacio baja california sur mexico observations on the feeding habits of the shark Heterodontus francisci girard 1854 chondrichthyes heterodontidae in san ignacio lagoon baja california sur mexico
    1996
    Co-Authors: J C Segurazarzosa, Felipe Galvanmagana, Leonardo Andres Abitiacardena, Gomez Palacio
    Abstract:

    A total of 108 stomach contents of horn shark (Heterodontus francisci Girard, 1854) from San Ignacio Lagoon were analyzed. The samples were taken seasonally from January 1992 to February 1993. This species occurred all year round, with low abundance in summer and fall. The index of relative importance (IRI) was used to determine the prey importance. The horn shark feeds mainly on

Jacob Geleijns - One of the best experts on this subject based on the ideXlab platform.