Bee diversity and richness decline as anthropogenic activity increases, confirm scientists

The researchers compared wild bee communities in the tropical dry forest of Mexico living in three habitat conditions: preserved vegetation, agricultural sites and urbanised areas

Changes in land use negatively affect bee species richness and diversity, and cause major shifts in species composition, reports a recent study of native wild bees, conducted at the Sierra de Quila Flora and Fauna Protection Area and its influence zone in Mexico.

Having registered a total of 14,054 individual bees representing 160 species, 52 genera, and five families over the span of a year, the scientists conclude that the studied preserved areas demonstrated “significantly greater” richness and diversity.

In their paper, published in the open-access Journal of Hymenoptera Research, a research team from the University of Guadalajara, Mexico, led by Alejandro Muñoz-Urias, compare three conditions within the tropical dry forest study site: preserved vegetation, an agricultural area with crops and livestock, and an urbanised area.

This bee species (Aztecanthidium xochipillium) is known exclusively from Mexico.

The researchers confirm earlier information that an increase in anthropogenic disturbances leads to a decrease in bee richness and diversity. While availability of food and nesting sites are the key factors for bee communities, changes in land use negatively impact flower richness and floral diversity. Thereby, turning habitats into urbanised or agricultural sites significantly diminishes the populations of the bees which rely on specific plants for nectar and pollen. These are the species whose populations are threatened with severe declines up to the point of local extinction.

According to their data, about half of the bees recorded were Western honey bees (49.9%), whereas polyester bees turned out to be the least abundant (1.2 %).

On the other hand, some generalist bees, which feed on a wide range of plants, seem to thrive in urbanised areas, as they take advantage of people watering wild and ornamental plants at times where draughts might be eradicating native vegetation.

“That is the reason why bees that can use a wide variety of resources are often able to compensate when circumstances change, although some species disappear due to land use changes,” explain the scientists.

This is a tropical dry forest in the dry (left) and rainy season (right).

In conclusion, the authors recommend that the tropical dry forests of both the study area and Mexico in general need to be protected in order for these essential pollinators to be conserved.

“Pollinators are a key component for global biodiversity, because they assist in the sexual reproduction of many plant species and play a crucial role in maintaining terrestrial ecosystems and food security for human beings,” they remind.

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Original source:

Razo-León AE, Vásquez-Bolaños M, Muñoz-Urias A, Huerta-Martínez FM (2018) Changes in bee community structure (Hymenoptera, Apoidea) under three different land-use conditions. Journal of Hymenoptera Research 66: 23-38. https://doi.org/10.3897/jhr.66.27367

Wildlife on the highway to hell: Roadkill in the largest wetland, Pantanal region, Brazil

Adult individual of Erythrolamprus aesculapii captured in roadside habitats of BR-262. Photo by Michel Passos

Scientists provide crucial data to prompt further conservation and safety measures at the notorious BR-262 highway

Having systematically monitored wild animals killed on the Brazilian federal highway BR-262, which passes through the Pantanal region, a research team from the Federal University of Mato Grosso do Sul, Brazil, published their data concerning birds and reptiles in the open access journal Check List.

Apart from information crucial for future conservation activities, the paper provides new and unexpected roadkill records, including the Black-and-white hawk-eagle.

Authored by Wagner Fischer and his colleagues Raquel Faria de Godoi and Antonio Conceição Paranhos Filho, the article is part of the first dataset of vertebrate mortality in the region. A separate paper of theirs is planned to present the data concerning mammals gathered during the same survey, which took place between 1996 and 2000.

An adult individual of Xenodon matogrossensis captured in roadside habitats of BR-262. Photo by Cyntia Santos.

Having mapped bird and reptile roadkill on the highway between the cities of Campo Grande and Corumbá in the Brazilian savannah, the team reports a total of 930 animals representing 29 reptile and 47 bird species. In addition, the data provide the first regional geographic record of the colubrid snake Hydrodynastes bicinctus.

The researchers conclude that the species richness observed in the road-killed animals clearly confirms earlier concerns about wildlife-vehicle collisions in the Pantanal region. Such accidents lead to long-term and chronic impact on both wildlife and road safety.

“Mitigation of wildlife-vehicle collisions on this road continues to claim urgency for biodiversity conservation and for human and animal safety and care,” say the authors.

“For managers, the main goal should be to determine target species of greatest concern, focusing on those vulnerable to local extinction or those which represent major risks of serious accidents.”

In the past, the team’s dataset had already been used as a guide to road fauna management. In particular, it was used by government road managers when planning animal overpassess and underpassess equipped with roadside fences as part of the long-term project Programa Estrada Viva: BR-262. So far, however, only some of the less efficient safety methods, such as road signs and lowered speed limits, have been applied at the most critical points.

Over the past several years, a few independent studies have been conducted to monitor roadkill in a similar manner. Two of them (2010 and 2017) looked into mammal-vehicle collisions, while the third recorded reptiles and birds as well. All of them serve to demonstrate that BR-262 continues to be a major cause for the regional wildlife mortality, which in turn increases the risks of serious accidents.

“BR-262 keeps its inglorious fame as a highway to hell for human and wild lives,” points out lead author Wagner Fischer.

Roadkill on the BR-262 highway, Pantanal region, Brazil. Photos by Ricardo Fraga and Wagner Fischer.

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Original source:

Fischer W, Godoi RF, Filho ACP (2018) Roadkill records of reptiles and birds in Cerrado and Pantanal landscapes. Check List 14(5): 845-876. https://doi.org/10.15560/14.5.845

First-ever fern checklist for Togo to help decision makers in the face of threats to biodiversity

Maidenhair fern (Adiantum schweinfurthii) occurring in dense forests.

Ferns and their allied species, which together comprise the pteridophytes, are vascular non-flowering plants that reproduce via spores. Many of their species are admired for their aesthetics.

However, despite being excellent bioindicators that allow for scientists and decision-makers to monitor the state of ecosystems in the face of climate change and global biodiversity crisis, these species are too often overlooked due to their relatively small size and lack of vivid colours.

Spike moss (Selaginella versicolor) with a preference for very humid and shaded forests.

To bridge the existing gaps in the knowledge about the diversity of ferns and their allied species, while also seeking to identify the ways these plants select their habitats and react to the changes occurring there later on, a research team from Togo and France launched an ambitious biodiversity project in 2013. As for the setting of their long-term study, they chose Togo – an amazingly species-rich country in Western Africa, whose flora expectedly turned out to be hugely understudied.

Having concluded their fern project in 2017, scientists Komla Elikplim Abotsi and Kouami Kokou from the Laboratory of Forestry Research, University of Lomé, Togo, who teamed up with Jean-Yves Dubuisson and Germinal Rouhan, both affiliated with the Institute of Systematics Evolution and Biodiversity (UMR 7205), France, have their first findings published in a taxonomic paper in the open access Biodiversity Data Journal.

In this first-of-a-kind checklist of Togolese ferns, the researchers record as many as 73 species previously not known to inhabit the country, including 12 species introduced for horticultural purposes. As a result of their 4-year study, the pteridophyte diversity of Togo – a country barely taking up 56,600 km² – now counts a total of 134 species.

Still, the authors believe that there are even more species waiting to be discovered on both national and global level.

“Additional investigations in the difficult to access areas of the far north of the country, and Togo Mountains are still needed to fill possible biodiversity data gaps and enable decision-makers to make the right decisions,” say the researchers.

The triangular staghorn species Platycerium stemaria living on a coffee tree branch.

In addition to their taxonomic paper, the authors are also set to publish an illustrated guide to the pteridophytes of Togo, in order to familiarise amateur botanists with this fascinating biodiversity.

 

Original source:
Abotsi KE, Kokou K, Dubuisson J-Y, Rouhan G (2018) A first checklist of the Pteridophytes of Togo (West Africa). Biodiversity Data Journal 6: e24137. https://doi.org/10.3897/BDJ.6.e24137

Museum collection reveals distribution of Carolina parakeet 100 years after its extinction

While 2018 marks the centenary of the death of the last captive Carolina parakeet – North America’s only native parrot, a team of researchers have shed new light on the previously known geographical range of the species, which was officially declared extinct in 1920.

Combining observations and specimen data, the new Carolina parakeet occurrence dataset, recently published in the open access Biodiversity Data Journal by Dr Kevin Burgio, , Dr Colin Carlson, University of Maryland and Georgetown University, and Dr Alexander Bond, Natural History Museum of London, is the most comprehensive ever produced.

The new study provides unprecedented information on the birds range providing a window into the past ecology of a lost species.

“Making these data freely available to other researchers will hopefully help unlock the mysteries surrounding the extinction and ecology of this iconic species. Parrots are the most at-risk group of birds and anything we can learn about past extinctions may be useful going forward,” says the study’s lead author, Kevin Burgio.

The observational recordings included in the study have been gleaned from a wide variety of sources, including the correspondence of well-known historical figures such as Thomas Jefferson and the explorers Lewis and Clark.

The study team referenced recorded sightings spanning nearly 400 years. The oldest recorded sighting dates back to 1564, and was found in a description of the current state of Florida written by Rene Laudonniere in 1602.

Alongside the written accounts, the researchers included location data from museum specimens. These include 25 bird skins from the Natural History Museum’s Tring site, whose skin collection is the second largest of its kind in the world, with almost 750,000 specimens representing about 95 per cent of the world’s bird species. Thereby, the study proves what invaluable resources museum collections can be.

“The unique combination of historical research and museum specimens is the only way we can learn about the range of this now-extinct species. Museums are archives of the natural world and research collections like that of the Natural History Museum are incredibly important in helping to increase our understanding of biodiversity conservation and extinction,” says Alex Bond.

“By digitising museum collections, we can unlock the potential of millions of specimens, helping us to answer some of today’s big questions in biodiversity science and conservation.”

It is hoped that this research will be the beginning of a wider reaching work that will explore further into the ecology of this long lost species.

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Original source:

Burgio KR, Carlson CJ, Bond AL (2018) Georeferenced sighting and specimen occurrence data of the extinct Carolina Parakeet (Conuropsis carolinensis) from 1564 – 1944. Biodiversity Data Journal 6: e25280. https://doi.org/10.3897/BDJ.6.e25280

Integration of Freshwater Biodiversity Information for Decision-Making in Rwanda

Teams from Ghana, Malawi, Namibia and Rwanda during the inception meeting of the African Biodiversity Challenge Project in Kigali, Rwanda. Photo by Yvette Umurungi.

The establishment and implementation of a long-term strategy for freshwater biodiversity data mobilisation, sharing, processing and reporting in Rwanda is to support environment monitoring and the implementation of Rwanda’s National Biodiversity Strategy (NBSAP). In addition, it is to also help us understand how economic transformation and environmental change is affecting freshwater biodiversity and its resulting ecosystem services.

As part of this strategy, the Center of Excellence in Biodiversity and Natural Resource Management (CoEB) at the University of Rwanda, jointly with the Rwanda Environment Management Authority (REMA) and the Albertine Rift Conservation Society (ARCOS), are implementing the African Biodiversity Challenge (ABC) project “Integration of Freshwater Biodiversity Information for Decision-Making in Rwanda.”

The conference abstract for this project has been published in the open access journal Biodiversity Information Science and Standards (BISS). 

The CoEB has a national mandate to lead on biodiversity data mobilisation and implementation of the NBSAP in collaboration with REMA. This includes digitising data from reports, conducting analyses and reporting for policy and research, as indicated in Rwanda’s NBSAP.

The collation of the data will follow the international standards and will be available online, so that they can be accessed and reused from around the world. In fact, CoEB aspires to become a Global Biodiversity Informatics Facility (GBIF) node, thereby strengthening its capacity for biodiversity data mobilisation.

Data use training for the African Biodiversity Challenges at the South African National Biodiversity Institute (SANBI), South Africa. Photo by Yvette Umurungi.

The mobilised data will be organised using GBIF standards, and the project will leverage the tools developed by GBIF to facilitate data publication. Additionally, it will also provide an opportunity for ARCOS to strengthen its collaboration with CoEB as part of its endeavor to establish a regional network for biodiversity data management in the Albertine Rift Region.

The project is expected to conclude with at least six datasets, which will be published through the ARCOS Biodiversity Information System. These are to include three datasets for the Kagera River Basin; one on freshwater macro-invertebrates from the Congo and Nile Basins; one for the Rwanda Development Board archive of research reports from protected areas; and one from thesis reports from master’s and bachelor’s students at the University of Rwanda.

The project will also produce and release the first “Rwandan State of Freshwater Biodiversity”, a document which will describe the status of biodiversity in freshwater ecosystems in Rwanda and present socio-economic conditions affecting human interactions with this biodiversity.

The page of Center of Excellence in Biodiversity and Natural Resource Management (CoEB) at University of Rwanda on the Global Biodiversity Information Facility portal. Image by Yvette Umurungi.

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The ABC project is a competition coordinated by the South African National Biodiversity Institute (SANBI) and funded by the JRS Biodiversity Foundation. The competition is part of the JRS-funded project, “Mobilising Policy and Decision-making Relevant Biodiversity Data,” and supports the Biodiversity Information Management activities of the GBIF Africa network.

 

Original source:

Umurungi Y, Kanyamibwa S, Gashakamba F, Kaplin B (2018) African Biodiversity Challenge: Integrating Freshwater Biodiversity Information to Guide Informed Decision-Making in Rwanda. Biodiversity Information Science and Standards 2: e26367. https://doi.org/10.3897/biss.2.26367

Scientists dive into museum collections to reveal the invasion route of a small crustacean

Biological invasions are widely recognised as one of the most significant components of global change. Far-reaching and fast-spreading, they often have harmful effects on biodiversity.

Therefore, acquiring knowledge of potentially invasive non-native species is crucial in current research. In particular, it is important that we enhance our understanding of the impact of such invasions.

To do so, Prof Sabrina Lo Brutto and Dr Davide Iaciofano, both working at the Taxonomy Laboratory of the University of Palermo, Italy, performed research on an invasive alien crustacean (Ptilohyale littoralis) known to have colonised the Atlantic European Coast. Their findings are published in the open access journal ZooKeys.

The studied species belongs to a group of small-sized crustaceans known as amphipods. These creatures range from 1 to 340 mm in length and feed on available organic matter, such as dead animals and plants. Being widely distributed across aquatic environments, amphipods have already been proven as excellent indicators of ecosystem health.

While notable for their adaptability and ecological plasticity, which secure their abundance in various habitats, these features also make amphipods especially dangerous when it comes to playing the role of invaders.

Having analysed specimens stored at the Museum of Natural History of Verona and the Natural History Museum in Paris, the scientists concluded that the species has colonised European waters 24 years prior to the currently available records.

The problem was that, back in 1985, when the amphipod was first collected from European coasts, it was misidentified as a species new to science instead of an invader native to the North American Atlantic coast.

A closer look into misidentified specimens stored in museum collections revealed that the species has been successfully spreading along the European coastlines.

Male of the invasive amphipod species (Ptilohyale littoralis), sampled in October 2015, from Bay of Arcachon, France.

Moreover, it was predicted that the amphipod could soon reach the Mediterranean due to the high connectivity between the sea and the eastern Atlantic Ocean through the Straits of Gibraltar – a route already used by invasive marine fauna in the past.

In the event that the invader reaches the Mediterranean, it is highly likely for the crustacean to meet and compete with a closely related “sister species” endemic to the region. To make matters worse, the two amphipods are difficult to distinguish due to their appearance and behaviour both being extremely similar.

However, in their paper, the scientists have also provided additional information on how to distinguish the two amphipods – knowledge which could be essential for the management of the invader and its further spread.

The authors believe that their study demonstrates the importance of taxonomy – the study of organism classification – and the role of natural history collections and museums.

“Studying and monitoring biodiversity can acquire great importance in European aquatic ecosystems and coastal Mediterranean areas, where biodiversity is changing due to climate change and invasions of alien species,” Prof Lo Brutto says. “In this context, specific animal groups play a crucial role in detecting such changes and they, therefore, deserve more attention as fundamental tools in biodiversity monitoring.”

“Regrettably, the steadily diminishing pool of experts capable of accurately identifying species poses a serious threat in this field.”

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Original source:

Lo Brutto S, Iaciofano D (2018) A taxonomic revision helps to clarify differences between the Atlantic invasive Ptilohyale littoralis and the Mediterranean endemic Parhyale plumicornis(Crustacea: Amphipoda). ZooKeys, 754: 47-62. https://doi.org/10.3897/zookeys.754.22884

Audit finds biodiversity data aggregators ‘lose and confuse’ data

In an effort to improve the quality of biodiversity records, the Atlas of Living Australia (ALA) and the Global Biodiversity Information Facility (GBIF) use automated data processing to check individual data items. The records are provided to the ALA and GBIF by museums, herbaria and other biodiversity data sources.

However, an independent analysis of such records reports that ALA and GBIF data processing also leads to data loss and unjustified changes in scientific names.

The study was carried out by Dr Robert Mesibov, an Australian millipede specialist who also works as a data auditor. Dr Mesibov checked around 800,000 records retrieved from the Australian MuseumMuseums Victoria and the New Zealand Arthropod Collection. His results are published in the open access journal ZooKeys, and also archived in a public data repository.

“I was mainly interested in changes made by the aggregators to the genus and species names in the records,” said Dr Mesibov.

“I found that names in up to 1 in 5 records were changed, often because the aggregator couldn’t find the name in the look-up table it used.”

data_auditAnother worrying result concerned type specimens – the reference specimens upon which scientific names are based. On a number of occasions, the aggregators were found to have replaced the name of a type specimen with a name tied to an entirely different type specimen.

The biggest surprise, according to Dr Mesibov, was the major disagreement on names between aggregators.

“There was very little agreement,” he explained. “One aggregator would change a name and the other wouldn’t, or would change it in a different way.”

Furthermore, dates, names and locality information were sometimes lost from records, mainly due to programming errors in the software used by aggregators to check data items. In some data fields the loss reached 100%, with no original data items surviving the processing.

“The lesson from this audit is that biodiversity data aggregation isn’t harmless,” said Dr Mesibov. “It can lose and confuse perfectly good data.”

“Users of aggregated data should always download both original and processed data items, and should check for data loss or modification, and for replacement of names,” he concluded.

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Original source:

Mesibov R (2018) An audit of some filtering effects in aggregated occurrence records. ZooKeys 751: 129-146. https://doi.org/10.3897/zookeys.751.24791

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.”

Image 2 Macropis on flower

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

Scientists use forensic technology to genetically document infanticide in brown bears

Modern open-source software helped the researchers identify the male that killed a female and her two cubs

Scientists used a technology designed for the purposes of human forensics, to provide the first genetically documented case of infanticide in brown bears, following the murder of a female and her two cubs in Trentino, the Italian Alps, where a small re-introduced population has been genetically monitored for already 20 years.

The study, conducted and authored by Francesca Davoli, The Italian Institute for Environmental Protection and Research (ISPRA), Bologna, and her team, is published in the open access journal Nature Conservation.

To secure their own reproduction, males of some social mammalian species, such as lions and bears, exhibit infanticidal behaviour where they kill the offspring of their competitors, so that they can mate with the females which become fertile again soon after they lose their cubs. However, sometimes females are also killed while trying to protect their young, resulting in a survival threat to small populations and endangered species.

“In isolated populations with a small number of reproductive adults, sexually selected infanticide can negatively impact the long-term conservation of the species, especially in the case where the female is killed while protecting her cubs,” point out the researchers.

“Taking this into account, the genetic identification of the perpetrators could give concrete indications for the management of small populations, for example, placing radio-collars on infanticidal males to track them,” they add. “Nevertheless, genetic studies for identifying infanticidal males have received little attention.”

Thanks to a database containing the genotypes of all bears known to inhabit the study site and an open-source software used to analyse human forensic genetic profiles, the scientists were able to solve the case much like in a television crime series.

orsa occultata - leggeraUpon finding the three corpses, the researchers were certain that the animals had not been killed by a human. In the beginning, the suspects were all male brown bears reported from the area in 2015.

Hoping to isolate the DNA of the perpetrator, the researchers collected three samples of hairs and swabbed the female’s wounds in search for saliva. Dealing with a relatively small population, the scientists expected that the animals would share a genotype to an extent, meaning they needed plenty of samples.

However, while the DNA retrieved from the saliva swabs did point to an adult male, at first glance it seemed that it belonged to the cubs’ father. Later, the scientists puzzled out that the attacker must have injured the cubs and the mother alternately, thus spreading blood containing the inherited genetic material from the father bear. Previous knowledge also excluded the father, since there are no known cases of male bears killing their offspring. In fact, they seem to distinguish their own younglings, even though they most likely recognise the mother.

To successfully determine the attacker, the scientists had to use the very small amount of genetic material from the saliva swabs they managed to collect and conduct a highly sophisticated analysis, in order to obtain four genetic profiles largely overlapping with each other. Then, they compared them against each of the males reported from the area that year. Eventually, they narrowed down the options to an individual listed as M7.

“The monitoring of litters is a fundamental tool for the management of bear populations: it has allowed the authors to genetically confirm the existence of cases of infanticide and in the future may facilitate the retrieval of information necessary to assess the impact of SSI on demographic trends,” conclude the researchers.

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Original source:

Davoli F, Cozzo M, Angeli F, Groff C, Randi E (2018) Infanticide in brown bear: a case-study in the Italian Alps – Genetic identification of perpetrator and implications in small populations. Nature Conservation 25: 55-75. https://doi.org/10.3897/natureconservation.25.23776

A race against pine: Wood-boring wasp in North America threatened by a Eurasian invader

Invasive species have diverse impacts in different locations, including biodiversity loss, as a result of native species being outcompeted for similar resources. A U.S. research team, led by Dr. Ann Hajek, Cornell University, studied the case of an aggressive Eurasian woodwasp that has recently established in North America and poses a threat to a native species. Their study is published in the open-access journal NeoBiota.

Most woodwasps play an essential part in the forest ecosystem, as they decompose wood, preferring dying or felled trees. They do so by laying their eggs in the wood underneath the tree bark. Curiously, the wasps also deposit a symbiotic fungus and venom that shuts down the tree’s defenses. As the tree weakens, the fungal infestation begins and the the tree starts to rot. When the eggs hatch, the larvae feed on the rotten wood before they emerge. This relationship is called obligate since the survival of the wasp is impossible without the fungal infestation.

IMG_2322Originating from Eurasia, the presence of the invasive species is dangerous because it can kill healthier pines. It has long been established in the southern hemisphere causing economic issues due to its attacks on pines. While pines have been introduced to that part of the world, they are native to North America, where the invasive wasp could be far more devastating.

Now that the invasive woodwasp has already been identified in the States, the scientists seek to find a way to protect its frail competitor, reporting a rapid decline in the North American species.

“We would often observe both species emerging from the same infested pine trees, but the ratios changed with time,” explains Dr. Ann Hajek.

“Shortly after the invasive colonizes an area, the native wasps emerging from the trees would equal the invasive. However, a few years later, the natives started to get fewer and fewer.”

It turned out that the Eurasian woodwasp has larger venom glands and produces more eggs, thanks to its greater body size. Furthermore, it emerges earlier than the North American species, so that it can find and colonize the most suitable trees first. By the time the native species lays its eggs, the authors speculate, most of the preferred trees are already occupied by the invasive, leaving a reduced supply of habitat for the newcomer’s larvae.

“Woodwasps are difficult to study and their biologies are generally poorly understood,” note the authors. “While the native species appears to be outcompeted from pines that both species prefer, it is possible that populations of the native can be sustained in trees less desirable to the invasive or unavailable during the time and place that the invasive is present.”

The scientists call for additional research on the native woodwasp in southeastern pine forests in USA, before the invaders spread to that area with extensive pine forests.

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Original source:

Hajek AE, Henry JC, Standley CR, Foelker CJ (2017) Comparing functional traits and abundance of invasive versus native woodwasps. NeoBiota 36: 39-55. https://doi.org/10.3897/neobiota.36.14953