Be prepared: Prioritising invasive species for strategic prevention in Durban, South Africa

Durban Harbour, used for both commercial and recreational purposes, is an important hub of human activity. The harbour was found to be an important point of first introduction as well as a site for naturalisation for the three species highlighted in this study.
(Photos by Şerban Procheş /left/ and Carl Munsamy /right/)

While exploring the way alien species invade cities around the world, South African PhD student Ashlyn L. Padayachee (University of KwaZulu-Natal, UKZN) and her supervisors, Serban Proches (UKZN) and John Wilson (SANBI and Stellenbosch University) remember suddenly being stricken.

What they realised was that while cities were gradually starting to prepare for climate change, their responses to invasions were rather reactive. Even though management focused on widespread invasive species, which were currently having the most negative impacts on native biodiversity, the researchers noted that if those decision makers had only targeted the next highly damaging invaders ahead of their arrival, the associated costs would have greatly decreased.

Consequently, the team developed a methodology, based on three key aspects: priority species, points of first introduction and sites of naturalisation, in order to identify the most probable and concerning invasive species for Durban (eThekwini in KwaZulu Natal), a coastal city in South Africa. Furthermore, their work, published in the open-access journal Neobiota provides decision makers from around the world with a new tool, that is easy to use and adjustable to the specificity of different cities.

Firstly, the researchers identified cities with a similar climate to Durban and used existing alien species watch lists, environmental criteria and introduction pathways to identify species, which are not present in South Africa, but are considered of unacceptable risk of invasion. The team continued by figuring out which of those selected species are likely to have pathways facilitating their introduction to the city and developed a climatic suitability model for each. Finally, the scientists linked the climate and pathway information, so that they could identify sites within Durban to be considered as a focus for the contingency planning for particular species.

As a result, the authors identified three alien species as priorities for Durban: Alligator weed (Alternanthera philoxeroides), American bullfrog (Lithobates catesbeianus) and the red imported fire ant (Solenopsis invicta).


River systems are ideal habitats for Alligator weed. River systems adjacent to points of first introduction were identified as important sites of first naturalisation of this species.
(Photo by Şerban Procheş)

In terms of points of introductions, the data highlighted the Durban Harbour, especially for the red imported fire ant. Plant nurseries and garden centres, as well as pet and aquarium shops were also identified as important sites for the three studied species. Additionally, suitable habitats located near the points of introduction, such as river systems and built infrastructure, were found in need of monitoring.


The red imported fire ant is usually found in close proximity to human dwellings, which provide ideal habitats for this species. Built infrastructure, especially those adjacent to the Durban Harbour, was identified as an important site of its naturalisation.
(Photo by Şerban Procheş)

In conclusion, the implementation of prioritisation schemes to consider the three aspects (species, pathways, and sites) allows managers to focus resources on those species which pose a greater risk of invasion and impact.

“This will only ever be one part of a broad range of biosecurity efforts, but it is one where, we believe, we can be prepared,” comment the authors.

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Original source:

Padayachee AL, Proches S, Wilson JRU (2019) Prioritising potential incursions for contingency planning: pathways, species, and sites in Durban (eThekwini), South Africa as an example. NeoBiota 47: 1-21. https://doi.org/10.3897/neobiota.47.31959

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.

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

 

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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

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

New light on the controversial question of species abundance and population density

Inspired by the negative results in the recently published largest-scale analysis of the relation between population density and positions in geographic ranges and environmental niches, Drs Jorge Soberon and Andrew Townsend Peterson of the University of Kansas, USA, teamed up with Luis Osorio-Olvera, National University of Mexico (UNAM), and identified several issues in the methodology used, able to turn the tables in the ongoing debate. Their findings are published in the innovative open access journal Rethinking Ecology.

Both empirical work and theoretical arguments published and cited over the last several years suggest that if someone was to take the distributional range of a species – be it animal or plant – and draw lines starting at the edges of the space inwards, they would find the species’ populations densest at the intersection of those lines. However, when the team of Tad Dallas, University of Helsinki, Finland, analysed a large dataset of 118,000 populations, equating to over 1,400 species of birds, mammals, and trees, they found no such relationship.

Having analysed the analysis, the American-Mexican team concluded that despite being based on an unprecedented volume of data, the earlier study was missing out some important points.

Firstly, the largest dataset used by Tad and his team comprises observational data which had not required a certain sampling protocol or a plan. Without any standard in use, it is easy to imagine that the observations would be predominantly coming from people around and near cities, hence strongly biased.

Additionally, the scientists note that the analysis largely disregards parts of species’ geographic distributions for which there were no abundant data. As a result, the range of a species could be narrowed down significantly and its centroid – misplaced. Meanwhile, the population would appear denser on what appears to be the periphery of the area.

Similar issue is identified in the localisation of populations in the environmental space, where once again their range turned out to have been represented as significantly smaller, when compared to data available from the International Union for Conservation of Nature (IUCN) and the Global Biodiversity Information Facility (GBIF).

Further, a closer look into the supplementary materials provided revealed that the precision of the population-density data was not scalable with the climate data. As a result, it is likely that multiple abundance data falls within a single climate pixel.

In conclusion, the authors note that in order to comprehensively study the abundance of a species’ populations, one needs to take into consideration a number of factors lying beyond the scope of either of the papers, including human impact.

“We suggest that this important question remains far from settled,” they say.

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Original source:

Soberón J, Peterson TA, Osorio-Olvera L (2018) A comment on “Species are not most abundant in the centre of their geographic range or climatic niche”. Rethinking Ecology 3: 13-18. https://doi.org/10.3897/rethinkingecology.3.24827

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.

Image 2On 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:Probennahme

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

Lion conservation requires effective international cooperation

Lions belong to the world’s most charismatic megafauna. However, lion numbers and range have declined alarmingly over the last two decades.

“To turn the tide, international cooperation is crucial,” says a team of lawyers, conservation biologists and social scientists.

In their recently published review article in the journal Nature Conservation, they assess the current and potential future role of international treaties regarding lion conservation.

Kruger 1To conduct this study, international wildlife lawyers Arie Trouwborst and Melissa Lewis from Tilburg Law School in the Netherlands teamed up with lion experts David Macdonald, Amy Dickman and other scientists from the University of Oxford‘s Wildlife Conservation Research Unit (WildCRU) – the research group that made Cecil the lion famous.

Their analysis clearly shows the importance of various global and regional treaties for lion conservation.

For instance, dozens of important lion areas have received international protection under treaties like the World Heritage Convention and the Ramsar Wetlands Convention, whereas trade in lion bones and hunting trophies is regulated through the Convention on International Trade in Endangered Species (CITES).

“There is still much room for improvement in the way the international commitments of lion range states are applied on the ground,” the review notes.

However, the authors conclude that it is worthwhile to invest in such improvements, and stress the importance of strategies involving the local people who live alongside lions. The review offers many concrete recommendations for optimising the contributions of the various treaties to lion conservation.

A particularly important recommendation is to formally list lions under the Convention on the Conservation of Migratory Species (CMS). A proposal to list lions is on the agenda of the next intergovernmental summit of the parties to the CMS in October this year.

As lead author Arie Trouwborst explains:

“Listing the lion would raise the profile of this iconic species, and would moreover enable the CMS to provide a framework for coordinating and assisting conservation efforts in the 25 countries where lions still occur in the wild.”Imfolozi 3

According to David Macdonald, Director of WildCRU:

“Biology is necessary, but not sufficient, to inform and deliver wildlife conservation. Our approach at the WildCRU in Oxford is holistic – this new partnership with international lawyers is a symbol of our determination to embrace knowledge from every discipline, leaving no stone unturned in our quest to conserve these iconic animals.”

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Original source:

Trouwborst A, Lewis M, Burnham D, Dickman A, Hinks A, Hodgetts T, Macdonald E, Macdonald D (2017) International law and lions (Panthera leo): understanding and improving the contribution of wildlife treaties to the conservation and sustainable use of an iconic carnivore. Nature Conservation 21: 83-128. https://doi.org/10.3897/natureconservation.21.13690

Conservation and nameless earthworms: Assessors in the dark?

Species that live exclusively in a single region are at a particular risk of extinction. However, for them to be protected, thorough assessments of the environmental impacts need to be performed.

There are more than 100 earthworm species living in the soil and dead wood of KwaZulu-Natal Province, South Africa. Most of them live exclusively in small regions in the province, which makes them extremely vulnerable.

To scientists Dr Adrian J. Armstrong, Ezemvelo KZN Wildlife, and Ms Thembeka Nxele, KwaZulu-Natal Museum, the problem is twofold. Firstly, they note that the expression “out of sight, out of mind” is very suitable for the case of the endemic earthworms in South Africa. Secondly, they point out that the lack of common names for these species is a stumbling block that hinders their inclusion in conservation assessments.

As a result, the researchers try to rectify this situation by assigning standardised English names to the endemic earthworms in KwaZulu-Natal. Their article is published in the open access journal African Invertebrates.

Scientific names are often intractable to non-specialists, and the lack of common names leaves environmental assessors in the dark when they need to figure out which earthworms may occur at a development site. In the meantime, it has been found that about 50% of the native vegetation in KwaZulu-Natal has already been removed as a result of infrastructure construction and the figure is rising.

“The indigenous earthworms generally don’t survive in developed areas,” say the authors.

For instance, the informal use of an English name (green giant wrinkled earthworm) for the species Microchaetus papillatus, has facilitated the inclusion of this species in environmental impact assessments in KwaZulu-Natal.

While the green giant wrinkled earthworm does occur in a relatively large and rapidly developing area in KwaZulu-Natal, other species live in smaller areas that have been urbanised even more.

The extinction of these earthworms is not only undesirable from the point of view of biodiversity advocates – the role of this group of soil organisms is impossible to replace fully with non-native earthworms. For example, some of the large indigenous earthworms (more than 1 m in length) burrow much deeper than the non-native species, thereby enriching and aerating the soil at greater depth.

The authors are hopeful that by giving the indigenous earthworms in KwaZulu-Natal common names, the threatened and endemic species will be conserved through inclusion in environmental impact assessments. Furthermore, they believe that earthworms could draw attention to the areas where they occur whenever a choice for new protected areas is to be made.

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Original source:

Armstrong AJ, Nxele TC (2017) English names of the megadrile earthworms (Oligochaeta) of KwaZulu-Natal. African Invertebrates 58(2): 11-20. https://doi.org/10.3897/AfrInvertebr.58.13226

New species of moth named in honor of Donald Trump ahead of his swearing-in as president

Days before Donald J. Trump steps forward on the Inaugural platform in Washington to assume the role of the 45th President of the United States of America, evolutionary biologist and systematist Dr. Vazrick Nazari named a new species in his honour. The author, whose publication can be found in the open access journal ZooKeys, hopes that the fame around the new moth will successfully point to the critical need for further conservation efforts for fragile areas such as the habitat of the new species.

While going through material borrowed from the Bohart Museum of Entomology, University of California, Davis, Dr. Vazrick Nazari stumbled across a few specimens that did not match any previously known species. Following thorough analysis of these moths, as well as material from other institutions, the scientist confirmed he had discovered the second species of a genus of twirler moths.

image 2While both species in the genus share a habitat, stretching across the states of California, USA, and Baja California, Mexico, one can easily tell them apart. The new moth, officially described as Neopalpa donaldtrumpi, stands out with yellowish-white scales present on the head in adults. In fact, it was in these scales that the author found an amusing reference to Mr. Trump’s hairstyle and turned it into an additional justification for its name.

Donald Trump’s flying namesake is announced only a month following the recently described species of basslet named after predecessor President Barack Obama, also published in ZooKeys. The fish is only known from coral reefs in the Papahānaumokuākea Marine National Monument, Northwestern Hawaii, a nature reserve which the 44th President of the United States of America expanded to become the largest protected marine area in the world.

Being a substantially urbanized and populated area, the habitat of N. donaldtrumpi is also under serious threat.

“The discovery of this distinct micro-moth in the densely populated and otherwise zoologically well-studied southern California underscores the importance of conservation of the fragile habitats that still contain undescribed and threatened species, and highlights the paucity of interest in species-level taxonomy of smaller faunal elements in North America,” says discoverer Dr. Vazrick Nazari. “By naming this species after the 45th President of the United States, I hope to bring some public attention to, and interest in, the importance of alpha-taxonomy in better understanding the neglected micro-fauna component of the North American biodiversity.”

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Original source:

Nazari V (2017) Review of Neopalpa Povolný, 1998 with description of a new species from California and Baja California, Mexico (Lepidoptera, Gelechiidae). ZooKeys 646: 79-94. https://doi.org/10.3897/zookeys.646.11411

Bee populations expanded during global warming after the last Ice Age

The Australian small carpenter bee populations appear to have dramatically flourished in the period of global warming following the last Ice Age some 18,000 years ago.

The bee species is found in sub-tropical, coastal and desert areas from the north-east to the south of Australia. Researchers Rebecca Dew and Michael Schwarz from the Flinders University of South Australia teamed up with Sandra Rehan, the University of New Hampshire, USA, to model its past responses to climate change with the help of DNA sequences. Their findings are published in the open access Journal of Hymenoptera Research.

“You see a rapid increase in population size from about 18,000 years ago, just as the climate began warming up after the last Ice Age,” says lead author Rebecca Dew. “This matches the findings from two previous studies on bees from North America and Fiji.”

“It is really interesting that you see very similar patterns in bees around the world,” adds Rebecca. “Different climate, different environment, but the bees have responded in the same way at around the same time.”

In the face of future global warming these finding could be a good sign for some of our bees.

However, the news may not all be positive. There are other studies showing that some rare and ancient tropical bees require cool climate and, as a result, are already restricted to the highest mountain peaks of Fiji. For these species, climate warming could spell their eventual extinction.

“We now know that climate change impacts bees in major ways,” says Rebecca, “but the challenge will be to predict how those impacts play out. They are likely to be both positive and negative, and we need to know how this mix will unfold.”

Bees are major pollinators and are critical for many plants, ecosystems, and agricultural crops.Image2

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Original source:

Dew RM, Rehan SM, Schwarz MP (2016) Biogeography and demography of an Australian native bee Ceratina australensis (Hymenoptera, Apidae) since the last glacial maximum. Journal of Hymenoptera Research 49: 25-41. doi: 10.3897/JHR.49.8066