scholarly journals Intra- and interspecific agonistic behaviour in hatchling Australian freshwater crocodiles (Crocodylus johnstoni) and saltwater crocodiles (Crocodylus porosus)

2013 ◽  
Vol 61 (3) ◽  
pp. 196 ◽  
Author(s):  
Matthew L. Brien ◽  
Grahame J. Webb ◽  
Jeffrey W. Lang ◽  
Keith A. Christian
Keyword(s):  
Interspecific Interactions ◽  
Open Water ◽  
Agonistic Behaviour ◽  
Agonistic Interactions ◽  
Crocodylus Johnstoni ◽  
Clear Winner ◽  
Crocodylus Porosus ◽  
Species Specific ◽  
High Level ◽  
Australian Freshwater

We examined agonistic behaviour in hatchling Australian freshwater crocodiles (Crocodylus johnstoni) at 2 weeks, 13 weeks, and 50 weeks after hatching, and between C. johnstoni and saltwater crocodiles (Crocodylus porosus) at 40–50 weeks of age. Among C. johnstoni, agonistic interactions (15–23 s duration) were well established by two weeks old and typically involved two and occasionally three individuals, mostly between 17 : 00 and 24 : 00 hours in open-water areas of enclosures. A range of discrete postures, non-contact and contact movements are described. The head is rarely targeted in contact movements with C. johnstoni because they exhibit a unique ‘head raised high’ posture, and engage in ‘push downs’. In contrast with C. porosus of a similar age, agonistic interactions between C. johnstoni were conducted with relatively low intensity and showed limited ontogenetic change; there was also no evidence of a dominance hierarchy among hatchlings by 50 weeks of age, when the frequency of agonistic interactions was lowest. Agonistic interactions between C. johnstoni and C. porosus at 40–50 weeks of age were mostly low level, with no real exclusion or dominance observed. However, smaller individuals of both species moved slowly out of the way when a larger individual of either species approached. When medium- or high-level interspecific interactions did occur, it was between similar-sized individuals, and each displayed species-specific behaviours that appeared difficult for contestants to interpret: there was no clear winner or loser. The nature of agonistic interactions between the two species suggests that dominance may be governed more strongly by size rather than by species-specific aggressiveness.

Morphometric analysis of the Australian freshwater crocodile (Crocodylus johnstoni)

2017 ◽  
Vol 65 (2) ◽  
pp. 97 ◽  
Author(s):  
Glenn P. Edwards ◽  
Grahame J. Webb ◽  
S. Charlie Manolis ◽  
Alex Mazanov
Keyword(s):  
Morphometric Analysis ◽  
Body Measurements ◽  
Body Parts ◽  
Allometric Growth ◽  
Relative Growth ◽  
Crocodylus Johnstoni ◽  
Arnhem Land ◽  
Freshwater Crocodile ◽  
Crocodylus Porosus ◽  
Australian Freshwater

We conducted a morphometric analysis of 279 Crocodylus johnstoni, using specimens from the McKinlay River (n = 265) and Arnhem Land (n = 14), to meet the management need for predicting body size of C. johnstoni from isolated body parts. The results also allow reconstruction of C. johnstoni dimensions for comparison with other crocodilian species. We detected sexual dimorphism in some body measurements from the McKinlay River, and geographic variation in the morphology of McKinlay River and Arnhem Land populations, but differences were slight. There is pronounced allometric growth in C. johnstoni in the immediate post-hatching phase, largely due to elongation of the snout after exiting the confines of the egg. We compared the size, shape and relative growth of C. johnstoni with that of other crocodilian species for which equivalent data are available, but particularly the other Australian crocodile, Crocodylus porosus. C. porosus has a proportionately longer tail and a shorter but wider snout than C. johnstoni, and we discuss possible ecological correlates of these and other differences.

Remote monitoring of crocodilians: implantation, attachment and release methods for transmitters and data-loggers

2009 ◽  
Vol 60 (4) ◽  
pp. 284 ◽  
Author(s):  
Craig E. Franklin ◽  
Mark A. Read ◽  
Peter G. Kraft ◽  
Niko Liebsch ◽  
Steve R. Irwin ◽  
...  
Keyword(s):  
Physiological Variables ◽  
Crocodylus Johnstoni ◽  
Data Loggers ◽  
Archival Tags ◽  
Crocodylus Porosus ◽  
Electronic Tags ◽  
Free Ranging ◽  
Australian Freshwater ◽  
Term Management

Crocodilians are by their very nature difficult animals to study. However, research on wild animals is essential for the development of reliable long-term management. Here, we describe methods for the acquisition and monitoring of behavioural and physiological variables from free-ranging crocodilians through the use of archival tags (data-loggers) and via satellite, radio and acoustic telemetry. Specifically, the attachment or implantation of electronic tags is described and examples provided of the type of data that can be collected. Our research group has used a combination of approaches to monitor the movements, diving activity, body temperatures and heart rates of crocodilians, including studies on the Australian freshwater crocodile (Crocodylus johnstoni), the estuarine crocodile (Crocodylus porosus) and the caiman (Caiman latirostris). Each approach or method presents unique challenges and problems, chiefly as a consequence of differences in body morphology and size of the crocodilian species, their behaviours and the habitats they occupy.

Out of sight or in too deep: Effect of visual barriers and water depth on agonistic behaviour and growth in hatchling saltwater crocodiles (Crocodylus porosus)

2014 ◽  
Vol 158 ◽  
pp. 102-110
Author(s):  
Matthew L. Brien ◽  
Christopher M. Gienger ◽  
Grahame J. Webb ◽  
Keith McGuinness ◽  
Keith A. Christian
Keyword(s):  
Water Depth ◽  
Agonistic Behaviour ◽  
Crocodylus Porosus

scholarly journals Effect of losing a fight on later agonistic behavior toward unfamiliar conspecifics in male Syrian hamsters

2011 ◽  
Vol 57 (4) ◽  
pp. 449-452 ◽  
Author(s):  
Javier Delbarco-Trillo ◽  
Robert E. Johnston
Keyword(s):  
Social Relationships ◽  
Syrian Hamster ◽  
Agonistic Behavior ◽  
Agonistic Interactions ◽  
Syrian Hamsters ◽  
The Third ◽  
Clear Winner ◽  
Male Subjects ◽  
Over Time

Abstract In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual (i.e., the familiar winner) but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had the opportunity to escape the winner. The next day the loser was paired with an unfamiliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day 1, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males.

Social allies modulate corticosterone excretion and increase success in agonistic interactions in juvenile hand-raised graylag geese (Anser anser)

2003 ◽  
Vol 81 (10) ◽  
pp. 1746-1754 ◽  
Author(s):  
Didone Frigerio ◽  
Brigitte Weiss ◽  
John Dittami ◽  
Kurt Kotrschal
Keyword(s):  
Life History ◽  
Foster Parent ◽  
Social Partner ◽  
Agonistic Behaviour ◽  
Agonistic Interactions ◽  
Anser Anser ◽  
Access To Resources ◽  
Standard Distance ◽  
Social Alliances ◽  
Corticosterone Metabolites

In mammals, support by a social partner may reduce stress levels and ease access to resources. We investigated the effects of the passive presence of a nearby social ally on excreted corticosterone immunoreactive metabolites and behaviour in juvenile graylag geese (Anser anser). Two groups of hand-raised juveniles (N1 = 9, N2 = 3) were tested over 1 year by positioning humans of different familiarity (i.e., the human foster parent, a familiar human, a nonfamiliar human, no human) at a standard distance to the focal geese. Their success in agonistic interactions significantly decreased with age and with decreasing familiarity of the accompanying human. The humans present modulated the excretion of corticosterone immunoreactive metabolites, with the strongest effects recorded after fledging when corticosterone metabolites were also positively correlated with agonistic behaviour. This suggests that a human foster parent may provide similar supportive benefits as goose parents do in natural families. We discuss the benefits of social alliances with regard to the integration into the flock, access to resources, and life history.

scholarly journals Resurrection of the Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832 (Teleostei, Serranidae) and its phylogenetic position within genus Serranus

ZooKeys ◽  
2021 ◽  
Vol 1017 ◽  
pp. 111-126
Author(s):  
Adriana Vella ◽  
Noel Vella ◽  
Carolina Acosta-Díaz
Keyword(s):  
Conservation Status ◽  
Valid Species ◽  
Phylogenetic Position ◽  
Mitochondrial Coi ◽  
Interspecific Divergence ◽  
Population Conservation ◽  
Status Assessment ◽  
Morphological Differences ◽  
Species Specific ◽  
High Level

The family Serranidae is represented by 92 genera and 579 valid species, with the genus Serranus Cuvier, 1816, containing 30 species. In this study, specimens of Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832, were collected from the Canary Islands and compared morphologically and genetically to Painted Comber, Serranus scriba (Linnaeus, 1758), from the Mediterranean Sea. Morphological differences, especially in the colour banding pattern, were corroborated by genetic differences in mitochondrial (COI and ND2) and nuclear (Rhod and PTR) markers. The mitochondrial DNA markers revealed a high level of divergence and no shared haplotypes between the two species (interspecific divergence: COI 4.31%; ND2 8.68%), and a phylogenetic analysis showed that these two species are closely related sister species sharing common ancestry. This study is therefore offering to resurrect S. papilionaceus Valenciennes, 1832 as a valid species increasing the number of eastern Atlantic Serranus species to 11. This should direct new species-specific research, including its population conservation status assessment across its distribution.

scholarly journals Development of species-specific Cichla species eDNA primers for alien invasive species (AIS) monitoring in Malaysia

2021 ◽  
Vol 4 ◽  
Author(s):  
O. Nurul Fizatul Nabilah ◽  
A. R. Ramizah ◽  
A. B. Adibah ◽  
S. Syazwan ◽  
A.G. Intan Faraha ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Environmental Dna ◽  
Coi Gene ◽  
Alien Invasive Species ◽  
Survey Method ◽  
Specific Primers ◽  
Invasive Fishes ◽  
Specific Amplification ◽  
Species Specific ◽  
High Level

Peacock bass or the cichlids are known locally as top predator fishes which are invasive in Malaysia freshwater system. Detection probabilities for these fishes are typically low, especially using conventional capture-survey method due to the fish’s behaviour of hiding beneath the water’s surface. Hence, the environmental DNA (eDNA) monitoring is a relatively new approach that can be used to assess the distribution of these invasive fishes. Here, we report the strategy to develop small fragment (280- 400 bp) specific-specific primers for three selected invasive Cichla species namely, C. ocellaris, C. monoculus, and C. kelberi based on mitochondrial DNA (mtDNA) sequences. Current research showed that the developed species-specific primers from cytochrome oxidase I (COI) gene has high resolution at species level. Species-specific amplification tests also proved the specificity of the developed primers, securing the high- level species identification potential which may help in controlling the spread of alien invasive fish species.

scholarly journals Ant-mediated seed dispersal in a warmed world

2013 ◽  
Author(s):  
Katharine L. Stuble ◽  
Courtney M. Patterson ◽  
Mariano A. Rodriguez-Cabal ◽  
Relena R. Ribbons ◽  
Robert R. Dunn ◽  
...  
Keyword(s):  
Climate Change ◽  
Seed Dispersal ◽  
Interspecific Interactions ◽  
Forest Site ◽  
Activity Levels ◽  
Seed Removal ◽  
Experimental Warming ◽  
Climatic Warming ◽  
Plant Seed ◽  
Species Specific

Climate change affects communities both directly and indirectly via changes in interspecific interactions. One such interaction that may be altered under climate change is the ant-plant seed dispersal mutualism common in deciduous forests of the eastern US. As climatic warming alters the abundance and activity levels of ants, the potential exists for shifts in rates of ant-mediated seed removal. We used an experimental temperature manipulation at two sites in the eastern US (Harvard Forest in Massachusetts and Duke Forest in North Carolina) to examine the potential impacts of climatic warming on overall rates of seed dispersal (using Asarum canadense seeds) as well as species-specific rates of seed dispersal at the Duke Forest site. We also examined the relationship between ant critical thermal maxima (CTmax) and the mean seed removal temperature for each ant species. We found that seed removal rates did not change as a result of experimental warming at either study site, nor were there any changes in species-specific rates of seed dispersal. There was, however, a positive relationship between CTmax and mean seed removal temperature, whereby species with higher CTmax removed more seeds at hotter temperatures. The temperature at which seeds were removed was influenced by experimental warming as well as diurnal and day-to-day fluctuations in temperature. Taken together, our results suggest that while temperature may play a role in regulating seed removal by ants, ant plant seed-dispersal mutualisms may be more robust to climate change than currently assumed.

scholarly journals LATEST INFORMATION ON THE DISTRIBUTION OF FUSARIUM LANGSETHIAE, THE PRODUCER OF T-2 AND HT-2 TOXINS, IN RUSSIA

2020 ◽  
Vol 103 (3) ◽  
pp. 201-206
Author(s):  
O. P. Gavrilova ◽  
T. Yu. Gagkaeva
Keyword(s):  
High Performance ◽  
Geographical Area ◽  
Intraspecific Diversity ◽  
Specific Primers ◽  
Toxic Metabolites ◽  
Central Regions ◽  
Species Specific ◽  
High Level ◽  
Grain Contamination ◽  
Fusarium Fungi

The annual monitoring of grain contamination with Fusarium fungi and the identification of their species composition showed the widespread distribution of F. langsethiae producing dangerous T-2 and HT-2 toxins in the Northwestern and Central regions of Russia. Mycological analysis of grain samples harvested in 2018–2019 allowed revealing the new places of F. langsethiae distribution, including Urals. The top infection rate of the oats grain by F. langsethiae in 2019 reached 14 %. The identification of F. langsethiae strains was supported by PCR with species-specific primers. The analysis of toxic metabolites in F. langsethiae by the combination of high-performance liquid chromatography and tandem mass spectrometry revealed the high level of T-2 and HT-2 toxins. The considerable total amounts of T-2 and HT-2 toxins (165–1230 μg/kg) were found in the grain samples infected with this species. Further clarification of the geographical area of F. langsethiae and the study of its intraspecific diversity are needed to understand the distribution of this toxin-producing fungus.

Sign in / Sign up

Export Citation Format

Share Document