Tag: Australia

Australian study into how seals react to boats prompts new ecotourism regulations

*Australian fur seals alert to the presence of the potential danger. Photo: Julia Back*

Unable to differentiate between a predator and a tourist boat carrying humans curious to view a colony of seals while resting in their natural habitat, pinnipeds are quick to react defensively as soon as they sense what they perceive as a potential life threat. The closer the vessel approaches, the more likely it is for the animals to rush into the sea in an attempt to escape and the greater the risk of injury and even death in the event of a stampede, or predation once they are in the water. In fact, just the act of remaining alert comes at potentially high energetic costs for the animals.

“Although the purpose of ecotourism is to give patrons the opportunity to observe animals in the wild engaging in typical behaviors, ecotourism-based human interactions may instead alter pinniped behavior by initiating responses indicative of predation avoidance,” explain the scientists.

“The periods fur seals spend ashore at colonies are particularly important for resting, evading predators, molting, breeding and rearing young. Fleeing behaviors in themselves expend energy, and time spent in the water as a result of flight responses can also be energetically costly,” they add.

*Australian fur seals begin to flee into the water as a boat approaches Kanowna Island. Photo: Julia Back*

To provide recommendations for appropriately informed management guidelines, so that ecotourism does not clashes with the animals’ welfare, the Australian research team of Julia Back and Prof John Arnould of Deakin University, Dr Andrew Hoskins, CSIRO, and Dr Roger Kirkwood, Phillip Island Nature Park, observed the response to approaching boats of a breeding colony of Australian fur seals on Kanowna Island in northern Bass Strait, southeastern Australia. Their study is published in the open-access journal Nature Conservation.

*A female Australian fur seal calling for her pup. Photo: Andrew Hoskins*

Whenever a seal detects a threat while onshore, they first change posture, watch the object and remain alert and vigilant until the danger is gone. In the field survey, such a response was triggered when the research boat approached the colony at a distance of 75 m. Interestingly, this reaction would be more pronounced in the morning (the researchers would normally visit the colony twice a day), while in the afternoon the seals would demonstrate a reduced response. Why this is so, remains unclear.

When there was only 25 m between the seals and the boat, the scientists observed many of the animals fleeing to the safety of the water. This kind of reaction is particularly dangerous for the seals and especially their young, as these animals tend to perceive risk based on the responses of the individuals around them. In such a cascading response, a large-scale stampede is likely to occur, where pups could easily get trampled to death or fall from cliffs.

“While the infrequency of these events suggests they are unlikely to have population-level effects, such disturbance impacts are in violation of state and federal regulations protecting marine mammals”, note the authors, citing the International Union for Conservation of Nature.

As a result of the study, the management guidelines were updated, so that they currently restrict boat approaches to 100 m at Kanowna Island from March through October, when the rearing of the pups takes place. During the breeding period, vessels need to keep a distance of at least 200 m, as previously.

In conclusion, the authors also note that their findings are limited to a single colony and are therefore insufficient to make any generalisations about other species or even other Australian fur seal populations.

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Original source:

Back JJ, Hoskins AJ, Kirkwood R, Arnould JPY (2018) Behavioral responses of Australian fur seals to boat approaches at a breeding colony. Nature Conservation 31: 35-52. https://doi.org/10.3897/natureconservation.31.26263

A new species of hard coral from the World Heritage-listed Lord Howe Island, Australia

The discovery of a new species of hard coral, found on Lord Howe Island, suggests that the fauna of this isolated location in the Tasman Sea off south eastern Australia is even more distinct than previously recognised.

In a recent paper in ZooKeys, Prof. Andrew Baird and Dr. Mia Hoogenboom from James Cook University, Townsville Australia and Dr. Danwei Huang from the National University of Singapore, describe the new species Cyphastrea salae.

“The animal itself is quite non-descript from a distance, although it is beautifully symmetrical up close like most corals,” says Dr. Hoogenboom. “But we believe this is the first of many new hard coral species to be found in this World Heritage-listed marine protected area.”

Lord Howe Island is famous for its many unique plant and animal species, known from nowhere else on Earth, including at least four species of palms, nine reef fish and 47 algae. However, the coral fauna remains largely unexplored, particularly using modern genetic techniques.

While some of the earliest work on coral reef ecology was done on Lord Howe Island, the species lists were compiled using a morphological taxonomy that has since been revised.

“On my very first dive in the lagoon at Lord Howe I knew I was looking at something very special,” says Prof. Baird. “Twenty years of diving all over the globe had not prepared me for what I saw. I could hardly put a name on any coral!”

Now, six years later, and largely due to the molecular skills of colleague Dr. Huang, the team is ready to name its first species.

“Interestingly, Cyphastrea salae looks almost exactly like other closely-related corals. However, its gene sequences are distinct and there is no doubt it is a species that is new to science,” says Dr. Huang.

The team now have hundreds of specimens to work through, but they are confident that there are more new coral species left to describe.

“The Acropora, in particular, look highly promisingly,” says Prof. Baird. “There are at least five species that look unlike anything I have seen anywhere else in my travels”.

Lord Howe Island lies over 900 km south of the next major area of coral diversity, the Great Barrier Reef, and therefore the populations on Lord Howe are highly isolated. Such isolation creates the potential for speciation, however, C. salae is the first new local coral species described to date. The discovery of this new species greatly increases the conservation significance of Lord Howe Island and reinforces the need for strong management measures to protect this unique fauna.

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Original source:

Baird AH, Hoogenboom MO, Huang D (2017) Cyphastrea salae, a new species of hard coral from Lord Howe Island, Australia (Scleractinia, Merulinidae). ZooKeys 662: 49-66. https://doi.org/10.3897/zookeys.662.11454

New land snail species from Australia shows dissection not necessary to identify molluscs

Dissection might prove unnecessary when identifying new molluscs after scientists Corey Whisson, Western Australian Museum, and Dr Abraham Breure, Naturalis Biodiversity Centre, the Netherlands, and Royal Belgian Institute of Natural Sciences, Belgium, described a previously unknown land snail based on its genitalia, yet without damaging the specimen in the slightest. The new species is published in the open access journal ZooKeys.

The biologists described the first new Australian land snail species of this family for the last 33 years thanks to micro-computed tomography (micro-CT) and reconstruction with specialised software. This novel method, likely applied for identification of molluscs for the first time in history, uses X-rays to create cross-sections of the genitalia, so that a 3D model can be created without damaging the specimen. This can be then compared to known related taxa’s genitalia in order to show if there are enough differences to prove species delimitation.

The scientists note that despite the satisfying results, micro-CT is time-consuming and “quite laborious” approach. “However, in the case of a single or just a few specimens, this may be an alternative to destructive dissection,” says Dr Abraham Breure in his personal blog.

The new land snail, called Bothriembryon sophiarum after Dr Abraham Breure’s wife Sophie J. Breure and Corey Whisson’s first daughter Sophie Jade Whisson, can only be found along a 180-kilometre line running across the escarpment and cliff tops of the Baxter Cliffs and Hampton Ranges in Western Australia. Given its restricted distributional range, it is considered a short-range endemic.

The mollusc is characterised with a slender high-spired shell, built specifically for the demanding nature of its habitat. Dwelling in rocky limestone substrate, which is often fractured with narrow cracks and fissures, the snail has developed a slender shell, so that it can move easily through cavities and under rocks. On the other hand, being predominantly cream in colour with reddish or greyish brown blotches, it successfully blends with the limestone.

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Original source:

Whisson CS, Breure ASH (2016) A new species of Bothriembryon (Mollusca, Gastropoda, Bothriembryontidae) from south-eastern Western Australia. ZooKeys 581: 127-140. doi:10.3897/zookeys.581.8044

Twenty-four new beetle species discovered in Australian rain forests

As many as twenty-four new species from Australian rainforests are added to the weevil genus Trigonopterus. Museum scientists Dr. Alexander Riedel, State Museum of Natural History Karlsruhe, Germany, and Rene Tanzler, Zoological State Collection Munich, Germany, have first discovered them among unidentified specimens in different beetle collections. The study is published in the open-access journal ZooKeys.

Australia is well known for its extensive deserts and savanna habitats. However, a great number of native Australian species are restricted to the wet tropical forests along the east coast of northern Queensland. These forests are also the home of the recent discoveries.

Most of the weevil species now recognised as new have already been collected in the 80s and 90s of the past century. Since then they had been resting in museum collections until German researcher Alexander Riedel had the opportunity to study them.

“Usually a delay of decades or even centuries occurs between the encounter of a new species in the field and its thorough scientific study and formal naming,” he explains. “This is due to the small number of experts who focus on species discovery,” he elaborates. “There are millions of unidentified insect specimens stored in collections around the world but only few people have the training necessary to identify those of special interest.”

However, old museum specimens alone are not enough either. Nowadays, researchers try to include DNA data in their descriptions, and the necessary sequencing techniques work more efficiently with freshly collected material. Therefore, the scientists set off to the field after they have studied the collections of others. Nevertheless, the German team were led to the discovery of one additional new species, which had never been seen before. They called itTrigonopterus garradungensis after the place where it was found.

All of the newly described weevils are restricted to small areas. Some are found only in a single locality. Presumably, this is a consequence of their winglessness, which has prevented them from spreading around. Furthermore, most of them dwell in the leaf litter where they are easily overlooked. Usually, they come to light during specific surveys of the litter fauna.

This is what Geoff Monteith from the Queensland Museum in Brisbane, for instance, has done in the past. As a result, his work is now relevant to conservation because highly localised species are extremely vulnerable to changes of their habitat such as climate change or the arrival of invasive species.

It is likely that Trigonopterus weevils have originated in Australia, the oldest landmass in the region. The island of New Guinea is geologically much younger, but there the genus has quickly enough diversified into hundreds of species. Studies investigating such evolutionary processes depend on names and clear diagnoses of the species. As a result of the present research, for the Australian fauna these are now available.

Besides the publication in the open-access journal ZooKeys, high-resolution photographs of each species are uploaded to the Species ID website, along with the scientific description. All this puts a face to the species name, and therefore is an important prerequisite for future studies on their evolution.

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Original Source:

Riedel A, Tanzler R (2016) Revision of the Australian species of the weevil genus Trigonopterus Fauvel. ZooKeys 556: 97-162. doi: 10.3897/zookeys.556.6126

Night calls reveal two new rainforest arboreal frog species from western New Guinea

Tracked by their calls at night after heavy rains, two species of narrow-mouthed frogs have been recorded as new. During the examinations it turned out that one of the studied specimens is a hermaphrodite and another one represents the first record of the genus Cophixalus for the Misool Island.

The field work, conducted by Steve Richards, South Australian Museum, Adelaide, and his team, took place in the Raja Ampat Islands, Indonesian part of New Guinea. Their findings, compiled by Dr. Rainer Guenther, Museum fur Naturkunde, Berlin, are available in the open access journal Zoosystematics and Evolution.

Belonging to the narrow-mouthed frog genus Cophixalus that occurs mainly in New Guinea and northern Australia, the two new species have been differentiated by their morphological features along with the specificity of their advertisement calls, produced by males to attract their partners. Both are characterised by small and slender bodies, measuring less than 23 mm in length.

Curious enough, when dissected one of the male specimens, assigned to the new species C. salawatiensis, revealed a female reproductive system with well-developed eggs. Simultaneously, neither its sound-producing organs, nor its calls differed in any way from the rest of the observed males from the same species. Therefore, it is to be considered a hermaphrodite.

Both new frog species have been retrieved from logged lowland rainforests. There the scientists noted that after heavy rains at night the males perched on leaves of bushes and produced sounds, characteristic for each species.

All specimens have been placed in the collection of the Museum Zoologicum Bogoriense (MZB) in Cibinong (Bogor), Indonesia.

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Original source:

Guenther R, Richards S, Tjaturadi B, Krey K (2015) Two new species of the genus Cophixalusfrom the Raja Ampat Islands west of New Guinea (Amphibia, Anura, Microhylidae).Zoosystematics and Evolution 91(2): 199-213.doi: 10.3897/zse.91.5411

Diggers from down under: 11 new wasp species discovered in Australia

After being mostly neglected for more than a hundred years, a group of digger wasps from Australia has been given a major overhaul in terms of species descriptions and identification methods. This approach has led to an almost 50% rise in the number of recognized species of these wasps on the continent. The study was published in the open access journal ZooKeys.

They call them with names like “Great Golden Digger” or “Great Black Wasp” in the US and there is a good reason behind it. However, some of these digger wasp species do not impress solely with their looks, but also with their wide range of distribution. Members of the wasp genusSphex can be found in almost every area of the world. Two researchers from the Museum für Naturkunde in Berlin, Thorleif Dörfel and Dr. Michael Ohl, have now reexamined the species diversity of Sphex in Australia.

More than a century has passed since the last revision of this group in the Down Under. Using pinned, dried individuals from museum collections all over the world, Dörfel and Ohl inspected over 900 specimens and recorded the morphological characters that they deemed most useful for species differentiation.

A very different lifestyle sets apart some species in the genus Sphex from the common idea that most people evoke on hearing the term “wasp”. Not being eusocial, each female constructs a separate, subterranean nest for their offspring, which is then filled with grasshoppers (or other insects, depending on the wasp species) that have been paralyzed by a sting as a food supply for the larvae. These wasps avoid contact with humans and generally do not show aggressive behavior toward us.

With 23 species known from Australia before this study, now the number has risen to 34. Most of these newly discovered species come from large quantities of material which had not been identified up to species level before. Dörfel and Ohl’s work also provides an up-to-date identification key, both in a regular and in an interactive form, that covers all known Australian species of the genus. Specifically designed to be easily usable and containing many helpful images, it can be utilized by anyone with even minimal prior training.

“Many insect groups are in urgent need of a revision or reclassification”, explained Thorleif Dörfel. “Our understanding of ecosystems depends on the ability to identify the species that are a part of them. The focus of this study was merely a single continent, but we are currently preparing a follow-up project in which we plan to examine representatives of this wasp genus from every major geographic area. Hopefully, this is going to help everybody who works on these animals, whether now or in another one hundred years.”

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Original source:

Dörfel TH, Ohl M (2015) A revision of the Australian digger wasps in the genus Sphex(Hymenoptera, Sphecidae). ZooKeys 521: 1-104. doi: 10.3897/zookeys.521.5995

Bush Blitz: The largest Australian nature discovery project finds 4 new bee species

Four new native bee species were recognised as part of the largest Australian nature discovery project, called ‘Bush Blitz‘. The South Australian bee specialists used molecular and morphological evidence to prove them as new. Three of the species had narrow heads and long mouth parts – adaptations to foraging on flowers of emu-bushes, which have narrow constrictions at the base. The new species are described in the open access journal ZooKeys.

Bees are important pollinators of crops and native plants, but habitat loss and pesticides are proved to be causing a serious decline in their populations in Europe and the United States of America. Meanwhile, the conservation status of native Australian bees is largely unknown because solid baseline data are unavailable and about one third of the species are as yet unknown to science. Furthermore, identification of Australian bees is hampered by a lack of keys for about half of the named species.

With their present publication, bee specialists Katja Hogendoorn (University of Adelaide), Remko Leijs and Mark Stevens (South Australian Museum) are now trying to make Australian native bees more accessible to the scientific community. The study introduces a new Barcoding of Life project, ‘AUSBS‘, which will be built to contain the barcode sequences of the identified Australian native bees.

In future, this database can help scientists who have molecular tools, but insufficient knowledge of bees, to identify known species. Yet, that is not the only use of the database. “Bee taxonomists can access and use the molecular information to answer specific problems, for example, how certain species are related or whether or not a male and female belong to the same species”, says Dr. Hogendoorn. “And combined with morphological information, the molecular database can help to identify new species”, she adds.

In their publication, the researchers demonstrate the utility of the database. After careful evaluation of the DNA sequence data and subsequent morphological comparison of the collected bees to museum type specimens, they recognised four new species in the genusEuhesma, which they subsequently described.

Three of the species belong to the group of bees that specialise on the flowers of emu-bushes. These bees have evolved narrow faces and very long mouth parts to collect the nectar through a narrow constriction at the base of the flowers. A similar evolution has been already observed in other groups of bees. The fourth species belongs to a different group within this large genus and has a normally shaped head.

So far, the project includes 271 sequences of 120 species that were collected during the Bush Blitz surveys, Australia’s largest nature discovery project. The researchers intend to build on the existing DNA database to cover as many as possible of the Australian species. “It is hoped that this will stimulate native bee research”, says Dr. Hogendoorn. “With about 750 Australian bee species still undescribed and many groups in need of revision there is an enormous job to do”, she concludes.

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Original source:

Hogendoorn K, Stevens M, Leijs R (2015) DNA barcoding of euryglossine bees and the description of new species of Euhesma Michener (Hymenoptera, Colletidae, Euryglossinae).ZooKeys 520: 41-59.doi: 10.3897/zookeys.520.6185

Under the wing of science: Two methods for aging nestling Carnaby’s cockatoo species

Multi-year research on two populations of the endangered endemic Carnaby’s cockatoo in southwestern Australia was conducted in order for two separate methods for nestlings aging to be assessed. If accurate enough, Dr. Denis Saunders and his team believe that the results could be vital in the threatened species’ preservation, as explained in the Carnaby’s cockatoo’s recovery plan.

One of the methods they have looked into is based on changes in the physical appearance of nestlings over the 10-11 week nestling period. The other relies on measurements of a nestling’s folded wing length and its comparison with growth curves from measurements of nestlings of known age. In their paper the Australian team also examines the timing and length of the egg-laying season. Their research is published in the open-access journal Nature Conservation.

The researchers point out that accurate nestling aging is essential for many ecological studies. The data could be used in investigating population dynamics, life histories, behaviour, longevity, conservation planning and management. It could also help in scheduling the visits of breeding areas so that the disturbance for the populations is minimised without compromising the results.

The scientists found out that observing the changes in a nestling’s size and feathers is less accurate than measuring the folded wing length. Its main disadvantage turned out to be the lack of distinguishable physical changes once the birds become about nine-week-old. However, “with experience it may be useful for gaining an approximation of the commencement and end of the breeding season without having to handle nestlings to take measurements,” the team says.

Their research on the egg-laying dates concluded that the most effective approach for examining nestlings is to conduct two visits per breeding season. Curiously, their findings showed that in wetter autumns the egg-laying begins earlier.

The team also suggests that their methods could be adopted for aging the currently under-researched closely related Baudin’s cockatoo until more species-specific technique is found.

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Original source:

Saunders DA, Dawson R, Nicholls AO (2015) Aging nestling Carnaby’s cockatoo, Calyptorhynchus latirostris, and estimating the timing and length of the breeding season.Nature Conservation 12: 27-42. doi: 10.3897/natureconservation.12.4863