Tag: ecology

Five new blanket-hermit crab species described 130 years later from the Pacific

A blanket-hermit crab grasping an anemone.

Since 1888, a lone crab species living in an extraordinary symbiosis has been considered to be one of its kind

At the turn of the twentieth century, two independent marine scientists – JR Henderson in 1888, and A Alcock in 1899, described two unusual blanket-hermit crabs from the Indo-West Pacific.

Unlike other hermit crabs, these extraordinary crustaceans do not search for empty shells to settle in for protection. Instead, they have developed a symbiotic relationship with sea anemones to cover their soft bellies. To do this, the crabs use highly specialized chelipeds to pull back and forth the anemone’s tissue to cover their soft bodies and heads whenever necessary – much like hiding under a blanket.

Among the numerous specimens collected during the famous HMS Challenger Expedition in 1874, there were two hermit crab specimens obtained from the Philippines. They amazed Henderson with their unusual physical characters, including an abdomen bent on itself rather than spirally curved, and the lack of any trace of either a shell or other kind of protective structure for their body.

As a result, in 1888, JR Henderson established a brand new genus and new species for it as Paguropsis typicus. The ending of the species name was subsequently grammatically corrected to Paguropsis typica.

A decade later, unaware of the previous discovery, A Alcock stumbled upon hundreds of hermit crab specimens off southern India, which exhibited quite spectacular behaviour. Having observed their symbiotic relations with sea anemones, the researcher also formally described in 1899 a new species and a new genus for his specimens.

However, shortly thereafter and upon learning of JR Henderson’s earlier work, A Alcock concluded that his hermit crab specimens and those of JR Henderson must be one and the same species, so the two scientific names were officially synonymized in 1901 in a publication with his colleague AF McArdle, with JR Henderson’s name taking precedence as required by the principle of priority set forth in the International Code of Zoological Nomenclature.

Now, 130 years later, an international team of scientists, led by invertebrate zoologist Dr Rafael Lemaitre of the National Museum of Natural History, Smithsonian Institution, USA, not only found that A Alcock’s Indian specimens were indeed a separate species, leading to the resurrection of its name as Paguropsis andersoni, but that blanket-hermit crabs are not as rare as previously thought.

In their recent publication in the open access journal ZooKeys, the biologists described a total of five new species and a new genus of closely related blanket-hermit crabs. Furthermore, they expect that other species are to be discovered, since there are many vast marine shelf areas and deep-sea habitats spread across the Indo-West Pacific yet to be sampled.

To develop their exceptional symbiosis with sea anemones, the blanket-hermit crabs have obviously needed just as extraordinary evolutionary adaptations. Perhaps the most remarkable of these are their specialized chelate fourth legs that allow for the crustaceans to effectively grab and stretch the thin-walled body of the anemones to cover themselves. For five of the species, the scientists report and unusual grasping shape for this cheliped that is reminiscent of bear claws, while in the other two the shape resembles ice-block tongs.

Unfortunately, the identity of the sea anemone species involved in the symbiotic relationship with any of the studied blanket-hermit crabs is currently uncertain, and their biology remains unknown.

A blanket-hermit crab 'wearing' an anemone. — A blanket-hermit crab ‘wearing’ an anemone.

So far, the genus described by JR Henderson as Paguropsis, contains five species distributed in the subtropical and tropical Indo-West Pacific, and living at depths ranging from 30 to 1125 m. These include the two species discovered in the 19th century, and three new species, one of which, Paguropsis gigas, is the largest known blanket-hermit crab that reaches a body size of 15 cm when fully stretched (a large size by hermit crab standards).

For two of the newly discovered hermit crabs, the new genus Paguropsina is erected to reflect the numerous similarities between the two species and their Paguropsis relatives. The Latin suffix -ina refers to the comparatively smaller size of the two species. Both blanket-hermit species of Paguropsina are found in the subtropical and tropical western Pacific at depth between 52 and 849 m.

“Here there is no shell to play the part of ‘Sir Pandarus of Troy,’ but the sea-anemone settles upon the hinder part of the young hermit-crab’s tail, and the two animals grow up together, in such a way that the spreading zoophytes form a blanket which the hermit can either draw completely forwards over its head or throw half-back, as it pleases,” Alcock once eloquently described his marine discovery.

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Original source:

Lemaitre R, Rahayu DL, Komai T (2018) A revision of “blanket-hermit crabs” of the genus Paguropsis Henderson, 1888, with the description of a new genus and five new species (Crustacea, Anomura, Diogenidae). ZooKeys 752: 17-97. https://doi.org/10.3897/zookeys.752.23712

A new hope: One of North America’s rarest bees has its known range greatly expanded

The Macropis Cuckoo Bee is one of the rarest bees in North America, partly because of its specialized ecological associations. It is a nest parasite of oil-collecting bees of the genus Macropis which, in turn, are dependent on oil-producing flowers of the genus Lysimachia.

In fact, the cuckoo bee – which much like its feather-bearing counterpart does not build a nest of its own, but lays its eggs in those of other species instead – is so rare that it was thought to have gone extinct until it was collected in Nova Scotia, Canada, in the early 2000s. As a result, the Macropis Cuckoo Bee was brought to the attention of the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).

Recently, an individual reported from Alberta, Canada, brought new hope for the survival of the species. In addition to previously collected specimens from Ontario, this record greatly expands the known range of the cuckoo.

Scientists Dr Cory S Sheffield, Royal Saskatchewan Museum, Canada, who was the one to rediscover the “extinct” species in Nova Scotia, and Jennifer Heron, British Columbia Ministry of Environment & Climate Change Strategy, present their new data, and discuss the conservation status of this species in their paper, published in the open access journal Biodiversity Data Journal.

“This species has a very interesting biology,” they say, “being a nest parasite – or cuckoo – of another group of bees that in turn have very specialized dietary needs.”

The hosts, bees of the genus Macropis (which themselves are quite rare) are entirely dependent on plants of the primrose genus Lysimachia. Moreover, they only go after those Lysimachia species whose flowers produce oil droplets, which the insects collect and feed to their larvae. Thus, Macropis bees require these oil-producing flowers to exist just like Macropis cuckoo bees need their hosts and their nests. Curiously, this reliance, as suggested by previous studies on related European species, has made the female cuckoos develop the ability to find their host’s nests by the smell of the floral oils.

“This level of co-dependence between flower, bee, and cuckoo bee, makes for a very tenuous existence, especially for the cuckoo,” the authors comment. “The recent specimen from Alberta lets us know that the species is still out there, and is more widespread than we thought.”

In conclusion, the authors suggest that continuing to monitor for populations of rare bees, and documenting historic records, are crucial for conservation status assessments of at-risk species.

“Biodiversity Data Journal provides a great venue to share this type of information with our colleagues for regional, national, and international efforts for species conservation,” they note.

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Original source:

Sheffield C, Heron J (2018) A new western Canadian record of Epeoloides pilosulus (Cresson), with discussion of ecological associations, distribution and conservation status in Canada. Biodiversity Data Journal 6: e22837. https://doi.org/10.3897/BDJ.6.e22837

The Alps are home to more than 3,000 lichens

Historically, the Alps have always played an emblematic role, being one of the largest continuous natural areas in Europe. With its numerous habitats, the mountain system is easily one of the richest biodiversity hotspots in Europe.

Lichens are curious organisms comprising a stable symbiosis between a fungus and one or more photosynthetic organisms, for example green algae and/or cyanobacteria. Once the symbiosis is established, the new composite organism starts to function as a whole new one, which can now convert sunlight into essential nutrients and resist ultraviolet light at the same time.

A common fruticose lichen in the Alps (Flavocetraria nivalis). Photo: Dr Peter O. Bilovitz — *A common fruticose lichen in the Alps (Flavocetraria nivalis).*
*Photo: Dr Peter O. Bilovitz*

Being able to grow on a wide range of surfaces – from tree bark to soil and rock, lichens are extremely useful as biomonitors of air quality, forest health and climate change.

Nevertheless, while the Alps are one of the best studied parts of the world in terms of their biogeography, no overview of the Alpine lichens had been provided up until recently, when an international team of lichenologists, led by Prof. Pier Luigi Nimis, University of Trieste, Italy, concluded their 15-year study with a publication in the open access journal MycoKeys.

Sunrise in the Julian Alps. Photo: Dr Pier Luigi Nimis — *Sunrise in the Julian Alps.*
*Photo: Dr Pier Luigi Nimis*

The scientists’ joint efforts produced the first ever checklist to provide a complete critical catalogue of all lichens hitherto reported from the Alps. It comprises a total of 3,138 entries, based on data collected from eight countries – Austria, France, Germany, Italy, Liechtenstein, Monaco, Slovenia and Switzerland. In their research paper, the authors have also included notes on the lichens’ ecology and taxonomy.

A common lichen in the Alps (Xanthoria elegans). Photo: Dr Tomi Trilar — *A common lichen in the Alps (Xanthoria elegans).*
*Photo: Dr Tomi Trilar*

They point out that such catalogue has been missing for far too long, hampering research all over the world. The scientists point out that this has been “particularly annoying”, since the data from the Alps could have been extremely useful for comparisons between mountainous lichen populations from around the globe. It turns out that many lichens originally described from the Alps have been later identified in other parts of the world.

“It was a long and painstaking work, which lasted almost 15 years, revealing a surprisingly high number of yet to be resolved taxonomic problems that will hopefully trigger further research in the coming years,” say the authors.

“We think that the best criterion to judge whether a checklist has accomplished its task for the scientific community is the speed of it becoming outdated,” they conclude paradoxically.

The new checklist is expected to serve as a valuable tool for retrieving and accessing the enormous amount of information on the lichens of the Alps

A widespread alpine lichen (Thamnolia vermicularis). Photo: Dr Peter O. Bilovitz — *A widespread alpine lichen (Thamnolia vermicularis).*
*Photo: Dr Peter O. Bilovitz*

that has accumulated over centuries of research. It offers a basis for specimen revisions, critical re-appraisal of poorly-known species and further exploration of under-explored areas. Thus, it could become a catalyst for new, more intensive investigations and turn into a benchmark for comparisons between mountains systems worldwide.

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Original source:

Nimis PL, Hafellner J, Roux C, Clerc P, Mayrhofer H, Martellos S, Bilovitz PO (2018) The lichens of the Alps – an annotated checklist. MycoKeys 31: 1-634. https://doi.org/10.3897/mycokeys.31.23568

Lichenologists at work in the Carnic Alps. Photo: Dr Pier Luigi Nimis — *Lichenologists at work in the Carnic Alps.*
*Photo: Dr Pier Luigi Nimis*

Double trouble: Invasive insect species overlooked as a result of a shared name

An invasive leaf-mining moth, feeding on cornelian cherry, has been gradually expanding its distributional range from its native Central Europe northwards for a period likely longer than 60 years. During that period, it has remained under the cover of a taxonomic confusion, while going by a name shared with another species that feeds on common dogwood.

To reproduce, this group of leaf-mining moths lay their eggs in specific plants, where the larvae make tunnels or ‘mines’, in the leaves. At the end of these burrows, they bite off an oval section, in which they can later pupate. These cutouts are also termed ‘shields’, prompting the common name of the family, the shield-bearer moths.

During a routine study into the DNA of leaf-mining moths, Erik van Nieukerken, researcher at Naturalis Biodiversity Center, Leiden, the Netherlands, discovered that the DNA barcodes of the species feeding on common dogwood and cornelian cherry were in fact so different that they could only arise from two separate species. As a result, Erik teamed up with several other scientists and amateur entomologists to initiate a more in-depth taxonomic study.

Curiously, it turned out that the two species had been first identified on their own as early as in 1899, before being described in detail by a Polish scientist in the 50s. Ironically, it was another Polish study, published in the 70s, that regarded the evidence listed in that description as insufficient and synonymised the two leaf-miners under a common name (Antispila treitschkiella).

Now, as a result of the recent study undertaken by van Nieukerken and his collaborators, the two moth species – Antispila treitschkiella and Antispila petryi – have their diagnostic features listed in a research article published in the open access journal Nota Lepidopterologica.

“We now establish that the species feeding on common dogwood, A. petryi, does not differ only in its DNA barcode, but also in characters of the larva, genitalia and life history,” explains Erik van Nieukerken. “A. petryi has a single annual generation, with larvae found from August to November, whereas A. treitschkiella, which feeds on cornelian cherry, has two generations, with larvae occurring in June-July and once again between September and November.”

While van Nieukerken and his team were working on the taxonomy of the moths, David C. Lees of the Natural History Museum, London, spotted a female leaf-miner in the Wildlife Garden of the museum. Following consultation with van Nieukerken, it turned out that the specimen in question was the first genuine A. treitschkiella ever to be found in Britain. Subsequently, the research groups decided to join forces, leading to the present discovery.

Despite the lack of data for the British Isles, it is already known that, in continental Europe, the cornelian cherry-feeding species had established in the Netherlands and much of Germany in the 1990s.

With common dogwood being widely planted, it is now suspected that A. petryi has recently reached Sweden and Estonia, even though there was no previous evidence of the leaf-miner expanding its range.

“This discovery should provoke the attention of gardeners and other members of the public alike to the invasive leafminers attacking some of our much admired trees and shrubs, as we have demonstrated for the cornelian cherry – a species well-known for its showy red berries in the autumn,” says David Lees.

“Especially in Britain, we hope that they check their photos for the conspicuous leaf mines, recognisable by those oval cutouts, to see if they can solve the mystery of when the invasion, which is now prominent on cornels around London, actually started, and how fast it progresses. Citizen scientists can help.”

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Original source:

van Nieukerken EJ, Lees DC, Doorenweerd C, Koster S(JC), Bryner R, Schreurs A, Timmermans MJTN, Sattler K (2018) Two European Cornus L. feeding leafmining moths, Antispila petryi Martini, 1899, sp. rev. and A. treitschkiella (Fischer von Röslerstamm, 1843) (Lepidoptera, Heliozelidae): an unjustified synonymy and overlooked range expansion. Nota Lepidopterologica 41(1): 39-86. https://doi.org/10.3897/nl.41.22264

Pan-European sampling campaign sheds light on the massive diversity of freshwater plankton

In a major pan-European study, a research team from Germany have successfully extracted environmental DNA (eDNA) from as many as 218 lakes to refute a long-year belief that vital microorganisms do not differ significantly between freshwater bodies and geographic regions the way plants and animals do.

Their new-age approach to biodiversity studies resulted in the largest freshwater dataset along with a study published in the open access journal Metabarcoding and Metagenomics.

Surface freshwaters are of critical importance for terrestrial life and, in particular, human life and welfare. However, these vital ecosystems are severely understudied, as compared to terrestrial or oceanic biomes, and so are the microbial organisms living in them.

On the other hand, it is these invisible to the naked eye creatures, called protists, that are responsible for keeping our ecosystems running. Their diversity and their high metabolic rates maintain ecosystem stability. In fact, microbes are the major source of the worlds oxygen.

In 2012, the team of Prof. Jens Boenigk, University of Duisburg-Essen, undertook the sampling campaign to study the distribution pattern of microbial organisms on a continental scale and the impact of Europe’s climatic history on their present-day whereabouts.

They sampled freshwater lakes and ponds from sites in Norway, Sweden, Germany, Poland, the Czech Republic, Slovakia, Hungary, Romania, Austria, Italy, France, Spain and Switzerland. Site selection focused on the European orogens, specifically the Alps, the Pyrenees, the Apennine, the High Tatras, the southern Scandinavian mountains and the connecting flatlands.

Thanks to the excellent collaboration both within the team and with a number of scientific institutions across Europe, which gave their support as access points for re-stocking sampling equipment and immediate sample preservation, the campaign delivered groundbreaking results illuminating the hidden diversity of the microbial biosphere.

The scientists reported that plankton diversity was highly partitioned between lakes which bear distinct biological fingerprints. In particular, high mountain ranges imprinted the microbial communities on both regional and continental scale. Ecological factors, such as temperature and nutrient concentrations, are well accepted factors structuring plankton communities.

Beyond the high plankton diversity and the associated highly specific community composition in distinct lakes, the plankton community composition revealed signals of the past, i.e. since the last glaciation some 12,000 years ago.

While this expedition yielded many new scientific findings, the scientists note that these are only the first results of this continental survey.

“We are well aware that we have only just begun our exploration of the hidden diversity of plankton diversity,” they conclude.

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Original source:

Boenigk J, Wodniok S, Bock C, Beisser D, Hempel C, Grossmann L, Lange A, Jensen M (2018) Geographic distance and mountain ranges structure freshwater protist communities on a European scale. Metabarcoding and Metagenomics 2: e21519. https://doi.org/10.3897/mbmg.2.21519

Special issue: Natura 2000 appropriate assessment and derogation procedure

The focus is on the case-law of the European Court of Justice and the German Federal Administrative Court

With over 27,500 sites, Natura 2000 is the greatest nature conservation network in the world. It covers more than 18 percent of the land area in the European Union and around 395,000 km2 of its marine territory.

Projects and plans within those sites or in their vicinity require an appropriate assessment to ensure that they will not have a significant impact on the integrity of a Natura 2000 site, according to Article 6(3) of the Habitats Directive 92/43/EEC. The Natura 2000 appropriate assessment is the central statutory instrument for the protection of the network, in addition to the general prohibition of deterioration.

An assessment must take place prior to the authorisation and implementation of a project or a plan. As a result of the European Court of Justice (ECJ) having maximised the effectiveness of the assessment by a stringent legal interpretation, a project or a plan must be rejected by the competent authorities if there is any remaining reasonable scientific doubt that it might adversely affect the integrity of the site.

Nevertheless, in accordance with the European principle of proportionality, the Habitats Directive does not intend to ban all human activity in Natura 2000 sites. This is the reason why, on the one hand, only significant adverse impacts on the integrity of a Natura 2000 site are relevant and, on the other, according to Article 6(4) Habitats Directive, a derogating authorisation is possible in favour of public interests.

However, numerous questions, which are relevant in practice, have so far only been considered by national courts. A special issue recently published with the open access journal Nature Conservation features a comprehensive review of the relevant case-law of the German Federal Administrative Court (BVerwG), which has thoroughly dealt with the Natura 2000 regime in a long series of judgements.

The author, Dr. Stefan Möckel of the Helmholtz-Centre for Environmental Research GmbH, Germany, is a long standing specialist in European and German nature conservation law. Within the four articles comprising the issue, he analyses the scope, procedural steps and requirements of the appropriate assessment and the derogation procedure. He also comments on the interpretations and practical solutions found by the ECJ and the BVerwG.

The first article explains the main steps and demands of the appropriate assessment. Questions on the scope of the terms “project” and “plan”, as well as determining significant impacts are discussed in greater detail in the second and third article. The fourth paper explores the requirements needed for a derogation to be approved.

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Original source:

Möckel S (2017) The European ecological network “Natura 2000” and the appropriate assessment for projects and plans under Article 6(3) of the Habitats Directive. In: Möckel S (Ed.) Natura 2000 appropriate assessment and derogation procedure – legal requirements in the light of European and German case-law. Nature Conservation 23: 1-29. https://doi.org/10.3897/natureconservation.23.13599

Möckel S (2017) The terms “project” and “plan” in the Natura 2000 appropriate assessment. In: Möckel S (Ed.) Natura 2000 appropriate assessment and derogation procedure – legal requirements in the light of European and German case-law. Nature Conservation 23: 31-56. https://doi.org/10.3897/natureconservation.23.13601

Möckel S (2017) The assessment of significant effects on the integrity of “Natura 2000” sites under Article 6(2) and 6(3) of the Habitats Directive. In: Möckel S (Ed.) Natura 2000 appropriate assessment and derogation procedure – legal requirements in the light of European and German case-law. Nature Conservation 23: 57-85. https://doi.org/10.3897/natureconservation.23.13602

Möckel S (2017) The European ecological network “Natura 2000” and its derogation procedure to ensure compatibility with competing public interests. In: Möckel S (Ed.) Natura 2000 appropriate assessment and derogation procedure – legal requirements in the light of European and German case-law. Nature Conservation 23: 87-116. https://doi.org/10.3897/natureconservation.23.13603

Rare footage of a new clearwing moth species from Malaysia reveals its behavior

Unique footage of a new species of clearwing moth has been recorded in a primeval rainforest in Peninsular Malaysia revealing the behaviour of this elusive insect.

Clearwing moths, which are day-flying insects belonging to the Sesiidae family, imitate bees and wasps. Apart from the common species considered as agricultural pests, these moths are known mainly from old museum specimens, stored on pins in forgotten drawers. In the wild, they are elusive creatures, rarely spotted and, hence, poorly studied.

Marta Skowron Volponi from the University of Gdansk, Poland, a PhD student specialising in entomology, teamed up with nature filmmaker and photographer Paolo Volponi, associated with the ClearWing Foundation for Biodiversity, to find these intriguing insects. The results of their studies were recently published in ZooKeys.

In their search for clearwing moths, they went deep into the virgin Malaysian jungle, where elephants, tigers, tapirs and other charismatic Southeast Asian animals roam, while dealing with the intense heat, humidity and countless blood-suckers.

In the end, however, their effort was worth it: on a bank of a crystal clear river, during the hottest hours of the day, the researchers discovered a new species of clearwing moth displaying behaviour known as mud-puddling.

“Mud-puddling is the process of sucking-up liquids in order to gain essential nutrients, such as salt or proteins”, explains Marta. “It has only recently been observed in clearwing moths and, similarly as in other Lepidopterans, it seems to be restricted to males”.

The newly discovered species was named Pyrophleps ellawi in honour of Marta and Paolo’s Malaysian friend EL Law who supported the team during their expeditions and who has a deep affinity for nature.

Curiously, rather than resembling a butterfly’s relative, the new moth looks like an insect from a whole different order. It mimics potter wasps.

“It has a slender body, long legs and transparent wings with a blue sheen in sunlight, similarly to some species of potter wasps”, says Marta.

Furthermore, while observing the moth in the wild, the authors noticed that it does not only look like a wasp – it also flies like one.

“There were potter wasps in the same area. In flight, the two insects were impossible to distinguish, they would always confuse us!”

The new species seems to be quite rare. During the authors’ three expeditions to Malaysia, they managed to see only eight individuals with each of them seen on a different day.

“So there we were: on our knees on a sandy beach, in the middle of the jungle, trying to film the 1.5 cm moth”, Marta recalls. “We didn’t have much time: a single clearwing would come around 2:00 PM and stay for several minutes only. We knew that once it flew away, we would not get another shot”.

“Could it be that their rarity is the reason why the behaviour of clearwing moths is practically unknown and why there are still new species waiting to be discovered?” the researchers wonder.

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Original source:

Skowron Volponi MA, Volponi P (2017) A new species of wasp-mimicking clearwing moth from Peninsular Malaysia with DNA barcode and behavioural notes (Lepidoptera, Sesiidae). ZooKeys692: 129-139. Doi: 10.3897/zookeys.692.13587

Do squirrels teach bears to cross the railroad? Grizzlies dig squirrel middens for grains

Grains have been reported to regularly trickle from hopper cars travelling via the railway located within the Canadian Banff and Yoho National Parks, attracting the local red squirrels.

As a result, the rodents have grown used to foraging on the spilled seeds, which they collect in underground storage areas where they can be discovered and dug up by grizzly bears. Grain-conditioned bears may frequent the railway more often than usual, resulting in increased mortality by trains strikes.

Furthermore, the dispersal, following caching and digestion of such seeds by both squirrels and bears, could lead to the spread and establishment of those agricultural plants in the area.

The case is investigated and discussed by members of the University of Alberta‘s research team of Julia Elizabeth Put, Laurens Put and Dr. Colleen Cassady St. Clair. Their study is published in the open access journal Nature Conservation.

It all began when members of the team found a grain-filled midden that was visited by a bear near where the same bear had bluff-charged Parks Canada employees. At the time, the researchers were investigating possible explanations for causes of grizzly bear mortality on the adjacent railway. Thus, an unexpected opportunity to document interactions between species and how those can lead to human-wildlife conflicts presented itself to the scientists.

The three basic questions brought up by Julia and her team were whether spilled grain could increase the number of squirrels near the rail; if other middens contained grain; and if other bears accessed grain in middens. Eventually, their data provided a resounding ‘yes’ to all of them.

In some mountain parks in North America, including Banff, grizzly bears are known to excavate squirrel middens to access whitebark pine seeds. The tree, however, is only found at high elevations far from the valley bottom where the railway is located. Nevertheless, this behaviour may easily translate to targeting other food items in middens, such as grain, speculate the researchers.

Once a bear consumes grain from a squirrel midden, it could initiate or reinforce a tendency to seek grain on the rail, where it is generally less concentrated. Such conditioning of food rewards could lead to grizzly bears spending more time in the area around or on the rails, where they would be at risk of being struck by trains.

“The only feasible mitigation for these effects is to reduce spillage from hopper cars via careful attention to loading and gate maintenance,” conclude the authors.

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Original source:

Put JE, Put L, St. Clair CC (2017) Caching behaviour by red squirrels may contribute to food conditioning of grizzly bears. Nature Conservation 21: 1-14. https://doi.org/10.3897/natureconservation.21.12429

Saving the Underworld: Clarifying the subterranean fauna classification for improved conservation

Inevitably, many habitats, including the particularly vulnerable subterranean ones, will continue being erased from our planet as a result of human activities and interests. The challenge is to protect the ones that are the sole habitats to certain organisms, so that their species are safe from extinction. Hence, it is essential that the distribution of every each one of them is clearly defined.

Brazilian scientists Prof. Eleonora Trajano, Universidade Federal de São Carlos, and Prof. Dr. Marcelo Rodrigues de Carvalho, Universidade de São Paulo, discuss the current classification system, its application and complexities in a paper published in the open access Subterranean Biology.

Nowadays, there are three categories of subterranean fauna accepted. Troglobites live exclusively underground and are usually characterised with reduced or lacking eyes and pale or transparent colors; troglophiles may live both in caves and on the surface, with individuals commuting between these habitats and promoting genetic interchange between subterranean and surface populations; trogloxenes use caves regularly, but must leave them periodically in order to complete their life cycle.

Throughout the years, many alterations and subdivisions have been applied to the classification used when determining whether a cave organism belongs exclusively to the subterranean habitat, or not, before concluding these three groups, also known as the Schiner-Racovitza system. It is important to separate them properly, since the destruction of a habitat to an endemic troglobite, for instance, would immediately wipe out its whole species, as it would be impossible for the animals to move away.

However, many historic publications do not feature enough details about the described species’ distribution, nor identification of the used classification, so that the information is unreliable. Furthermore, there have been times, when people have been even afraid to survey the underground habitats, led by beliefs and associations linking caves to the “World of the Dead”.

In their paper, the authors conclude that the only way to define the species status of subterranean organisms with certainty is to study each species’ dynamics over a period of at least three years, since animals may migrate on a seasonal and/or non-seasonal basis. Also, scientists need to study thoroughly the area outside the surveyed cave, while testing for sampling sufficiency at all times.

“When employing classifications of subterranean organisms, especially for conservation purposes, these conditions should be checked for reliability of the status attributed to them,” say the authors. “Misplacing these organisms within the Schiner-Racovitza categories impairs the efficiency of such policies.”

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Original source:

Trajano E, Carvalho MR (2017) Towards a biologically meaningful classification of subterranean organisms: a critical analysis of the Schiner-Racovitza system from a historical perspective, difficulties of its application and implications for conservation. Subterranean Biology 22: 1-26. https://doi.org/10.3897/subtbiol.22.9759

Bee species with little known nesting-behavior observed to use plastic instead of leaves

Little is known about the nesting activities of some lineages of megachiline bees. Dr. Sarah Gess, affiliated with both Albany Museum and Rhodes University, South Africa, and Peter Roosenschoon, Conservation Officer at the Dubai Desert Conservation Reserve, United Arab Emirates, made use of their earlier observations gathered during a survey on flower visitation in the spring of 2015, to fill some gaps in the knowledge of of three species from such lineages.

Among their findings, published in the open access Journal of Hymenoptera Research, is a curious instance of a bee attempting to build brood cells using green pieces of plastic. Having examined two nests of the leafcutter bee species Megachile (Eurymella) patellimana, they report that one of the females nested in burrows in compacted sandy ground beneath a plant, and the other – in the banks of an irrigation furrow.

However, while the former was seen carrying a freshly cut leaf, the latter seemed to have discovered a curious substitute in the form of green plastic. Later on, upon checking the nest, the researchers found that the phenomenon they had observed was no isolated incident – at least six identical pieces of narrow, tough, green plastic were grouped together in an apparent attempt to construct a cell. It turns out that the bee had been deliberately cutting off approximately 10-milimetre-long pieces with its large and strong toothed mandibles, before bringing them back to the nest.

“Although perhaps incidentally collected, the novel use of plastics in the nests of bees could reflect ecologically adaptive traits necessary for survival in an increasingly human-dominated environment,” the authors quote an earlier study.

The two studied mason bee species (Megachile (Maximegachile) maxillosa and Pseudoheriades grandiceps) were seen to construct their nests using a mixture of resin and sand in pre-existing cavities, such as trap-nests, above the ground. The researchers note that resin is a common nest-building material among numerous species of mason bees, also known as resin bees. Previously, it has been suggested that apart from making the nest waterproof, the plant secretions may contain substances that fend off parasites.

The authors’ earlier paper exploring the flower visitation by bees and wasps in the Dubai Desert Conservation Reserve is also published in the open-access Journal of Hymenoptera Research.

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Original source:

Gess SK, Roosenschoon PA (2017) Notes on the nesting of three species of Megachilinae in the Dubai Desert Conservation Reserve, UAE. Journal of Hymenoptera Research 54: 43-56. https://doi.org/10.3897/jhr.54.11290