Man’s best friend could be a jaguar’s next meal: A case study from the Mexican Caribbean

Events of jaguars predating on and attacking dogs are poorly documented throughout the Americas. Researchers from Mexico and Germany report in detail jaguar attacks on 20 dogs at a tourist site in the Mexican Caribbean. In addition, they describe an initiative proposed by locals as well as national and international NGOs to prevent human-jaguar conflicts due to pet predation. The study was published in the open-access journal Neotropical Biology and Conservation.

Mahahual is a small fishing village in the Mexican Caribbean that receives a large number of tourists every year. Over the past 15 years, its population has increased rapidly, and, as a result, people have started to settle in areas away from the main center of the village, sometimes encroaching on jaguar habitats. As most of those people keep guard dogs on their properties, jaguars have taken advantage of this situation by wandering near people’s houses at night, and sometimes those dogs end up as a night-time snack for the big cats.

A jaguar is photographed wandering around houses looking for dogs. Photo by Víctor Rosales

Unlike jaguar attacks on livestock, attacks and predation on other domestic species such as dogs have only been documented anecdotally (through interviews or from remains found in faeces). Such attacks can indeed lead to pet predation conflict, which can ultimately have a negative impact on the jaguar populations. Attachment to pets may lead humans to start killing the big cats, which is of particular concern for an endangered species like the jaguar. Furthermore, it is possible that a wide range of pathogens may be transmitted from dogs to jaguars, further threatening the health of jaguar populations in Mahahual.

A dog injured as a result of a jaguar attack in Mahahual, Quintana Roo, Mexico. Photo by Víctor Rosales

This is why a multidisciplinary team made up of veterinarians, conservationists, locals, NGOs (Aak Mahahual A.C. and International Fund for Animal Welfare (IFAW)) and researchers (El Colegio de la Frontera Sur and Universidad Tecnológica de Calakmul), led by Dr Jonathan Pérez Flores, began investigating the occurrence of jaguar predation and attacks on dogs at the Mexican Caribbean tourist site from almost 10 years ago. Their research was just published in the open-access journal Neotropical Biology and Conservation.

According to their report, the behaviour of Mahahual’s jaguars resembles that of Indian leopards, which have already turned dogs into an important component of their diet, preferring them over livestock. Jaguars and leopards usually attack from a blindside, biting the dogs on the neck or head to avoid counterattacks. Similarly to leopards, jaguars attack at night and kill more dogs during the dry season. This is likely due to the fact that it’s easier for jaguars to hunt dogs than their natural prey: armadillo, lowland paca, brocket deer, white-tailed deer. Furthermore, the latter are less available during the dry season.

One of the night houses built by the people of Mahahual, Aak Mahahual A.C. and International Fund for Animal Welfare (IFAW). Photo by Francisco Rubén Castañeda

In 2017, the people of Mahahual partnered with Aak Mahahual A.C. and IFAW to build protective night houses made of wood and wire mesh meant to keep dogs safe at night. So far, they’ve built 38 such houses to prevent jaguar attacks. Sterilisation and vaccination campaigns have also been intensified since late 2020 to prevent the transmission of diseases between the two species.

Thanks to this study, we now have a better understanding of the adaptability and persistence of jaguars in human-dominated landscapes and the impact of dog predation by jaguars. However, the authors call for more research in the area to help paint the full picture.

Research article:
Carral-García M, Buenrostro I, Weissenberger H, Rosales V, Pérez-Flores J (2021) Dog predation by jaguars in a tourist town on the Mexican Caribbean. Neotropical Biology and Conservation 16(4): 461-474. https://doi.org/10.3897/neotropical.16.e68973

Two new pit vipers discovered from Qinghai-Tibet Plateau

Two new species of venomous snakes were just added to Asia’s fauna – the Nujiang pit viper from Tibet, and the Glacier pit viper found west of the Nujiang River and Heishui, Sichuan.

Guest blog post by Jingsong Shi

Two new species of venomous snakes were just added to Asia’s fauna – the Nujiang pit viper (Gloydius lipipengi) from Zayu, Tibet, and the Glacier pit viper (G. swild) found west of the Nujiang River and Heishui, Sichuan, east of the Qinghai-Tibet Plateau. Our team of researchers from the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences and Bangor University published the discovery in the open-access journal ZooKeys. In this study, we performed a new molecular phylogenetic analysis of the Asian pit vipers.

Glacier pit viper (Gloydius swild)

The Nujiang pit viper has a greyish brown back with irregular black ring-shaped crossbands, wide, greyish-brown stripes behind the eyes, and relativity short fangs, while the Glacier pit viper is blueish-grey, with zigzag stripes on its back, and has relatively narrow stripes behind its eyes.

Nujiang pit viper (Gloydius lipipengi)

Interestingly, the Glacier pit viper was found under the Dagu Holy-glacier National Park: the glacier lake lies 2000 meters higher than the habitat of the snakes, at more than 4,880 m above sea level. This discovery suggests that the glaciers might be a key factor to the isolation and speciation of alpine pit vipers in southwest China.

The glacier lake on top of the mountain near the type locality of Glacier pit viper.

The stories behind the snakes’ scientific names are interesting too: with the new species from Tibet, Gloydius lipipengi, the name is dedicated to my Master’s supervisor, Professor Pi-Peng Li from the Institute of Herpetology at Shenyang Normal University, just in time for Li’s sixtieth birthday. Prof. Li has devoted himself to the study of the herpetological diversity of the Qinghai-Tibet Plateau, and it was under his guidance that I became an Asian pit viper enthusiast and professional herpetological researcher. 

Gloydius swild, the new species from Heishui, Sichuan, is in turn named after the SWILD Group, which studies the fauna and biodiversity of southewst China. They discovered and collected the snake during an expedition to the Dagu Holy-glacier.

A misty morning near the habitat of Glacier pit viper.

We are equally impressed by the sceneries we encountered during our field work: throughout our journey, we got to look at sacred, crystal-like glacier lakes embraced by the mountains, morning mist falling over the village, and colorful broadleaf-conifer forests. During our expedition, we met a lot of hospitable Tibetan inhabitants and enjoyed their kindness and treats, which made the expedition all the more unforgettable.

Research article:

Shi J-S, Liu J-C, Giri R, Owens JB, Santra V, Kuttalam S, Selvan M, Guo K-J, Malhotra A (2021) Molecular phylogenetic analysis of the genus Gloydius (Squamata, Viperidae, Crotalinae), with description of two new alpine species from Qinghai-Tibet Plateau, China. ZooKeys 1061: 87-108. https://doi.org/10.3897/zookeys.1061.70420

Journal Alpine Entomology calls for contributions in a new topical collection

“Trends in Arthropods of Alpine Aquatic Ecosystems” is the first topical collection for the journal of the Swiss Entomological Society

“Trends in Arthropods of Alpine Aquatic Ecosystems” is the first topical collection for the journal of the Swiss Entomological Society

The open-access, peer-reviewed scholarly journal Alpine Entomology, published by Pensoft on behalf of the Swiss Entomological Society, announced its very first topical collection of articles, which will be focusing on arthropods associated with aquatic ecosystems in mountainous regions.

The journal is currently inviting scientists, working on aquatic fauna from alpine habitats, to openly publish their research articles and short notices that provide evidence how arthropods’ biogeography, species communities, distribution, behaviour and morphology have changed in recent times. 

“Aquatic invertebrates are key indicators of global or local changes. Furthermore, many aquatic ecosystems are closely linked to mountains because they originate in them. Many valuable unpublished datasets on aquatic arthropod fauna may therefore be available from mountainous regions,”

explain the rationale behind the newly opened topical article collection guest editors Dr. Jean-Luc Gattolliat (Museum of Zoology, Lausanne and University of Lausanne, Switzerland) and Dr. David Muranyi (Eszterházy Károly Catholic University, Hungary).

The aim of the “Trends in Arthropods of Alpine Aquatic Ecosystems” collection is to bring together data and findings about what many agree is the most impacted type of environment on Earth: aquatic ecosystems, especially running waters.

The collection will remain open for submissions for the next two years. In the meantime, the accepted manuscripts will be published on a rolling basis, as soon as they are ready for publication.

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Visit the journal’s website at: https://alpineentomology.pensoft.net/ 
Follow Alpine Entomology on Twitter and Facebook.

New BiCIKL project to build a freeway between pieces of biodiversity knowledge

Within Biodiversity Community Integrated Knowledge Library (BiCIKL), 14 key research and natural history institutions commit to link infrastructures and technologies to provide flawless access to biodiversity data.

In a recently started Horizon 2020-funded project, 14 European institutions from 10 countries, representing both the continent’s and global key players in biodiversity research and natural history, deploy and improve their own and partnering infrastructures to bridge gaps between each other’s biodiversity data types and classes. By linking their technologies, they are set to provide flawless access to data across all stages of the research cycle.

Three years in, BiCIKL (abbreviation for Biodiversity Community Integrated Knowledge Library) will have created the first-of-its-kind Biodiversity Knowledge Hub, where a researcher will be able to retrieve a full set of linked and open biodiversity data, thereby accessing the complete story behind an organism of interest: its name, genetics, occurrences, natural history, as well as authors and publications mentioning any of those.

Ultimately, the project’s products will solidify Open Science and FAIR (Findable, Accessible, Interoperable and Reusable) data practices by empowering and streamlining biodiversity research.

Together, the project partners will redesign the way biodiversity data is found, linked, integrated and re-used across the research cycle. By the end of the project, BiCIKL will provide the community with a more transparent, trustworthy and efficient highly automated research ecosystem, allowing for scientists to access, explore and put into further use a wide range of data with only a few clicks.

“In recent years, we’ve made huge progress on how biodiversity data is located, accessed, shared, extracted and preserved, thanks to a vast array of digital platforms, tools and projects looking after the different types of data, such as natural history specimens, species descriptions, images, occurrence records and genomics data, to name a few. However, we’re still missing an interconnected and user-friendly environment to pull all those pieces of knowledge together. Within BiCIKL, we all agree that it’s only after we puzzle out how to best bridge our existing infrastructures and the information they are continuously sourcing that future researchers will be able to realise their full potential,” 

explains BiCIKL’s project coordinator Prof. Lyubomir Penev, CEO and founder of Pensoft, a scholarly publisher and technology provider company.

Continuously fed with data sourced by the partnering institutions and their infrastructures, BiCIKL’s key final output: the Biodiversity Knowledge Hub, is set to persist with time long after the project has concluded. On the contrary, by accelerating biodiversity research that builds on – rather than duplicates – existing knowledge, it will in fact be providing access to exponentially growing contextualised biodiversity data.

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Learn more about BiCIKL on the project’s website at: bicikl-project.eu

Follow BiCIKL Project on Twitter and Facebook. Join the conversation on Twitter at #BiCIKL_H2020.

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The project partners:

The first Field Identification Guide of Seychelles’ deeper reefscapes

The deep ocean is the last frontier on our planet. It is home to creatures beyond our imagination and filled to the brim with life. Coastal communities have known the value of a healthy ocean for centuries, yet much of its life remains unknown, sitting beyond the reach of most research programs due to the hostility of its depth and vastness. With current research and monitoring activities in the region mostly focussing on shallow reefs, our Field Identification Guide, published in the peer-reviewed, open-access Biodiversity Data Journal, aims to showcase the benthic organisms that inhabit the Seychelles’ deeper reefscapes. The research cruise that gathered the imagery data used to create the guide, Nekton’s “First Descent: Seychelles Expedition”, was the first of its kind to systematically survey deeper reefs in Seychelles waters, bringing to light previously little-known ecosystems and their inhabitants.

Guest blog post by Nico Fassbender, Zoleka Filander, Carlos Moura, Paris Stefanoudis and Lucy Woodall

 “We cannot protect something we do not love, we cannot love what we do not know, and we cannot know what we do not see.”

These compelling words by author Richard Louv perfectly describe the importance of taxonomy in today’s conservation efforts.

A fan coral of the genus Annella surrounded by various smaller fans and encrusting benthic organisms. Photograph taken at 60m depth. © Nekton.

The deep ocean is the last frontier on our planet. It is home to creatures beyond our imagination and filled to the brim with life. Coastal communities have known the value of a healthy ocean for centuries, yet much of its life remains unknown, sitting beyond the reach of most research programs due to the hostility of its depth and vastness. 

More recently, the importance of deeper ecosystems started moving into the focus of modern marine research as many scientists across the globe are now working to unriddle the mysteries and processes that drive the patterns of life down in the deep.

Deeper reef habitats, starting at ~30m depth beyond SCUBA diving limits, are of crucial importance for coastal communities and adjacent ecosystems alike. They have been found to not only support coral and fish larval supply, aiding shallower reefs, but also to act as a refuge for many species in times of disturbance. Yet, going back to the start of this post – you cannot protect what you don’t know – and we currently know very little about these deeper reefs, especially ones in the Western Indian Ocean region.

We are many nations, but together we are one ocean.

Zoleka Filander – Department of Forestry, Fisheries and Environment, Branch Oceans and Coasts, Cape Town, South Africa

With current research and monitoring activities in the region mostly focussing on shallow reefs, our Field Identification Guide, published in the peer-reviewed, open-access Biodiversity Data Journal, aims to showcase the benthic organisms that inhabit the Seychelles’ deeper reefscapes. The research cruise that gathered the imagery data used to create the guide, Nekton’s “First Descent: Seychelles Expedition”, was the first of its kind to systematically survey deeper reefs in Seychelles waters, bringing to light previously little-known ecosystems and their inhabitants.

All species play relevant roles in trophic relations, in the functioning of ecosystems, and all have a potential biotechnological interest.

Carlos Moura – OKEANOS/DOP, University of the Azores, Horta, Portugal
A grouper (Cephalopholis miniate) hovering above encrusting benthic communities at Aldabra, dominated by the scleractinian coral Pachyseris. Photograph taken at 30m depth. © Nekton.

Our Field Identification Guide is one of the first efforts to describe the mesophotic and sub-mesophotic reefs in the Western Indian Ocean. To effectively protect these ecosystems, stakeholders need to be able to visualise them and scientists need to be able to identify and classify the organisms they observe. Displaying the diversity of the benthic organisms we encountered is only the first step in a complex and long process, allowing us to categorize, study, monitor and thus effectively protect these habitats. 

The correct identification of life is a fundamental building block of ecological knowledge. This international collaboration provided an important place to start from when considering the life on deeper reefs in Seychelles and the wider Western Indian Ocean region.

Lucy Woodall – University of Oxford, and Nekton

To survey the benthic flora and fauna of the Seychelles, we used a variety of methods, including submersibles, remotely operated vehicles and SCUBA diving teams equipped with stereo-video camera systems. We then recorded benthic communities during transect surveys conducted at 10 m, 30 m, 60 m, 120 m, 250 m and 350 m depths. This way, we ended up with 45 h of video footage and enough images to be able to present a photographic guide for the visual identification of the marine macrophytes, corals, sponges and other common invertebrates that inhabit Seychelles’ reefs.

We encountered coral fan gardens on steep slopes, boulders entirely encrusted with sponges of all colours and textures, corals of all shapes and sizes, and an amazing variety of critters. The images in our guide cannot do justice to the beauty of these habitats, and more than one tear was shed encountering these intact ecosystems teeming with life. Especially in times of increasingly frequent disturbance events and quickly shifting baselines (i.e., what we would see as a pristine, healthy reef in the 21st century), intact reef systems become increasingly rare. So much so that they are often confined to extremely remote and/or long and heavily protected areas. Finding these deeper reefs intact and with little to no signs of anthropogenic disturbance means hope – hope that there are yet undiscovered and unexplored reefs in the Western Indian Ocean region that show similar traits; and hope that we will discover even more novel habitats worth protecting.

An overview of how habitat composition changes across depths at Astove Island. © Nekton.

We hope that this guide will help the public to discover the beauty of Seychelles’ deeper reefs and aid current and future monitoring and research activities in Seychelles and the Western Indian Ocean region.

Currently, there are few formalised training materials available to new marine researchers working in mesophotic and deeper reef habitats, especially for the Indian Ocean. The present benthic field ID guide will hopefully be of use to marine researchers, managers, divers and naturalists with the identification of organisms as seen in marine imagery or live in the field.

Paris Stefanoudis – University of Oxford, and Nekton

Taxonomic paper:

Fassbender N, Stefanoudis PV, Filander ZN, Gendron G, Mah CL, Mattio L, Mortimer JA, Moura CJ, Samaai T, Samimi-Namin K, Wagner D, Walton R, Woodall LC (2021) Reef benthos of Seychelles – A field guide. Biodiversity Data Journal 9: e65970. https://doi.org/10.3897/BDJ.9.e65970

The journal Biosystematics and Ecology moves to ARPHA Platform

The scholarly publisher and technology provider Pensoft and its self-developed publishing platform ARPHA welcome Biosystematics and Ecology – a journal by the Austrian Academy of Sciences – to its growing open-access scholarly portfolio. By moving to ARPHA, Biosystematics and Ecology now enjoys a long list of high-tech perks, which dramatically enhance the entire publishing process, from submission to publication, distribution and archiving.

The Austrian Academy of Sciences’ journal Biosystematics and Ecology now boasts an improved publishing infrastructure after moving to the technologically advanced ARPHA Platform and signing with publisher and technology provider Pensoft. The publisher, well-established in the domain of biodiversity-themed journals, is eager to welcome this latest addition to its growing open-access portfolio.

Biosystematics and Ecology is a continuation and replaces the established print-only Biosystematics and Ecology Series of the Austrian Academy of Sciences’s Commission for Interdisciplinary Ecological Studies. It publishes research focused on biodiversity in Central Europe and around the world, a domain of rapidly growing importance as а global biodiversity crisis is looming. A great advantage of Biosystematics and Ecology, in contrast to its predecessor, is the ability to simply update existing checklists and therefore to account for new scientific findings about taxonomic groups or regions. 

The peer-reviewed outlet includes contributions on a wide range of ecology and biosystematics topics, aiming to provide biodiversity data, such as catalogi, checklists and interdisciplinary research to the scientific community, while offering the maximum in accessibility, usability, and transparency. The journal is currently indexed in Crossref and archived in CLOCKSS, Portico and Zenodo.

Having already acquired its own glossy and user-friendly website provided by ARPHA, the journal also takes advantage of the platform’s signature fast-track publishing system, which offers an end-to-end publishing solution from submission to publication, distribution and archiving. The platform offers a synergic online space for authoring, reviewing, editing, production and archiving, ensuring a seamlessly integrated workflow at every step of the publishing process.

Thanks to the financial support of the Academy, Biosystematics and Ecology will publish under Diamond Open Access, which means that it is free to read and publish. Opting for ARPHA’s white-label publishing solution, the journal is published under the Academy’s branding and imprint, while benefiting from all signature high-tech features by ARPHA.

Biosystematics and Ecology also makes use of ARPHA Preprints, another platform developed by Pensoft, where authors can post a preprint in a matter of seconds upon submitting a manuscript to the journal. Once the associated manuscript gets published, the preprint is conveniently linked to the formal paper, displaying its citation details.

ARPHA’s easy-to-use, open-access publishing platform offers high-end functionalities such as diverse paper formats (PDF, machine-readable JATS XML, and semantically enriched HTML), automated data export to aggregators, web-service integrations with major global indexing databases, advanced semantics publishing, and automated email notifications and reminders. Features like these make it easy for both humans and machines all over the world to discover, access, cite, and reuse published research.

Two new tree species discovered in Colombia

Trees of the genus Otoba have small, foul-smelling flowers coloured in yellow or greenish yellow, and round, aromatic fruits. Toucans, monkeys, or small terrestrial animals sometimes feed on their fruits, while herbivorous insects have developed a taste for their leaves. Part of the nutmeg family, Otoba trees are widely distributed from Nicaragua to Brazil, with as many as nine species native to Colombia.

Fruits of Otoba from Osa Peninsula, Costa Rica. Photo by Reinaldo Aguilar

Despite this apparent abundance, though, scientific knowledge on their biology is very limited.

Thanks to researchers from the Louisiana State University and the Missouri Botanical Garden, we now know more about these interesting trees, as Daniel Santamaría-Aguilar and Laura P. Lagomarsino recently described two new species of Otoba in the open-access, peer-reviewed journal PhytoKeys.

Even though the COVID-19 pandemic meant limited access to physical specimens, the research team were able to identify the two new species while investigating herbaria samples. This discovery helps clear some taxonomic confusions in the genus, as both of these new species had often been mistaken for other Otoba members.

The newly described Otoba scottmorii and Otoba squamosa can be found in Colombia’s Antioquia department, growing in premontane and humid forests. Known from the premontane forests of Cordillera Occidental in Colombia, Otoba squamosa grows at 1330–1450 m, while Otoba scottmorii, locally known as Cuángare otobo, grows in the humid forests in the Department of Antioquia, northwestern Colombia.

Staminate flowers of Otoba from Osa Peninsula, Costa Rica. Photo by Reinaldo Aguilar

The scientific name scotmorii is a tribute to Dr. Scott A. Mori (1941–2020), “a wonderful person and skilled botanist; a dedicated explorer of Central and South America humid forests (where this species occurs), especially in the Guianas and the Amazon basin; and an authority on Neotropical Lecythidaceae,” who inspired and personally supported Daniel Santamaría-Aguilar in his botanical work.

Because their habitats are threatened by deforestation, both tree species are preliminarily assessed as Endangered according to the criteria of the International Union for Conservation of Nature.

Research article:

Santamaría-Aguilar D, Lagomarsino LP (2021) Two new species of Otoba (Myristicaceae) from Colombia. PhytoKeys 178: 147-170. https://doi.org/10.3897/phytokeys.178.64564

From an amateur nature video to a unique study on Antarctic jellyfish

Sometimes research emerges from the strangest turns of events. In this case, an online video created by an amateur videographer on life under the sea ice in McMurdo Sound, Antarctica, resulted in a unique taxonomic study on Antarctic jellyfish and an image-based training set for machine learning. This study was published in the open-access Biodiversity Data Journal.

Sometimes, scientific discoveries emerge from the strangest turns of events.

It all started in 2018, when Dr. Emiliano Cimoli, postdoctoral researcher at the University of Tasmania, joined a field campaign to McMurdo Sound in the Ross Sea, Antarctica – to study not jellyfish, but rather the algal communities that thrive beneath the ice. 

This crystal-like comb jelly species, Callianira cristata, has been reported for the first time in the Ross Sea by the team of researchers. Photo by Dr. Emiliano Cimoli

“These algae are like the plants of the under-ice world and are very important for the Antarctic food chain,” Dr. Cimoli says.  The research team he was part of focused on the development of new sensing technologies to monitor these algal communities (e.g. optical techniques and chemical microsensors).

“We usually have a nice large tent to be able to work and operate such instruments in the harsh Antarctic environment. The cool part is that inside this tent, we have a massive 2 x 2 m hole in the sea ice that allows us to deploy these instruments to the under-ice world.”

It’s kind of like a magic portal to another world filled with mysterious and wondrous jellyfish-like creatures that live down there.

Besides working as an engineer and remote sensing scientist, Dr. Cimoli is also a passionate amateur nature and wildlife photographer and videographer, and in his free time he decided to document all sightings of these creatures with his camera. The researcher used a combination of macro photography equipment and a set of light sources, along with underwater robots for filming underwater. 

This brownish-orange comb jelly of the genus Beroe is likely one of the five undescribed species characterized by the team of researchers. Photo by Dr. Emiliano Cimoli

“Finally, I ended up having a massive amount of jellyfish footage, did not know what to do with it, then lockdown hit and suddenly I found myself working on a trippy video composition of all these creatures,” he adds.

The value of his video was soon picked up by biologist Dr. Gerlien Verhaegen, postdoctoral researcher at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC):

“When I came across Emiliano’s video, I was amazed by the image quality of his underwater footage. You could clearly distinguish some key morphological features.” Unlike hard-bodied animals, the fragile body of jellyfishes and comb jellies (i.e. “sea gooseberries”) are easily destroyed when sampled with nets, which is why photography and videography of specimens are crucial to describing them taxonomically.

“Life Beneath the Ice”, a short musical film about light and life beneath the Antarctic sea-ice by Dr. Emiliano Cimoli

The two postdocs soon joined forces to produce a collaborative study. 

“I think I underestimated the time needed to produce a jellyfish taxonomic paper,” laughs Dr. Verhaegen. “Most of the original descriptions of Antarctic jellies date back to the so-called Heroic Age of Antarctic Exploration in the early 20th century, and are written in English, French, and German. Furthermore, due to the high-water content of jellies, it is extremely difficult to fix and preserve them in formalin or ethanol. We therefore could not compare our specimens to physical specimens preserved in museums but had to rely on the century old descriptions and drawings. Luckily, we were in good hands with my project host, Dr. Dhugal Lindsay, senior scientist at JAMSTEC, a jellyfish taxonomist expert, and last author of our paper”.

Filming creatures in their natural environment can yield valuable information on their trophic interactions with other organisms. For example, this picture of a Diplulmaris antarctica jellyfish shows it feeds on comb jellies, with a Beroe present in its stomach, whereas numerous hyperiid amphipods (small parasitic crustaceans) are observed scattered around on the bell of the jellyfish. Photo by Dr. Emiliano Cimoli

Despite the small geographical and temporal scale of this study, which was published in the open-access Biodiversity Data Journal, a total of 12 species were reported, with two jellyfish and three comb jellies likely representing undescribed species.

Besides revealing new morphological traits for every species, including some behavior and trophic traits, this study was also the first to include a training image set for video annotation of Antarctic jellyfish through machine learning. 

“Machine learning is being applied to numerous fields nowadays, from voice recognition software and translation through to detection of typhoon formation,” comments Dr. Lindsay.

“In marine biology, annotating species from underwater videos can be both time-consuming and financially costly, with very few experts able to give names to the high diversity of species invariably encountered. Machine learning techniques could help solve these issues by enabling automatic first-pass annotation of videos. However, taxonomically accurate image-based datasets are needed to train these learning algorithms, and this study is a valuable first step.”

Watch the video “Life Beneath the Ice” by Dr. Emiliano Cimoli on YouTube and Vimeo.

Original source

Verhaegen, G., Cimoli, E., & Lindsay, D. J. (2021). Life beneath the ice: jellyfish and ctenophores from the Ross Sea, Antarctica, with an image- based training set for machine learning. Biodiversity Data Journal, 9, e69374. https://doi.org/10.3897/BDJ.9.e69374

One water bucket to find them all: Detecting fish, mammals, and birds from a single sample

Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study.

Revolutionary environmental DNA analysis holds great potential for the future of biodiversity monitoring, concludes a new study

Collection of water samples for eDNA metabarcoding bioassessment.
Photo by Till-Hendrik Macher.

In times of exacerbating biodiversity loss, reliable data on species occurrence are essential, in order for prompt and adequate conservation actions to be initiated. This is especially true for freshwater ecosystems, which are particularly vulnerable and threatened by anthropogenic impacts. Their ecological status has already been highlighted as a top priority by multiple national and international directives, such as the European Water Framework Directive.

However, traditional monitoring methods, such as electrofishing, trapping methods, or observation-based assessments, which are the current status-quo in fish monitoring, are often time- and cost-consuming. As a result, over the last decade, scientists progressively agree that we need a more comprehensive and holistic method to assess freshwater biodiversity.

Meanwhile, recent studies have continuously been demonstrating that eDNA metabarcoding analyses, where DNA traces found in the water are used to identify what organisms live there, is an efficient method to capture aquatic biodiversity in a fast, reliable, non-invasive and relatively low-cost manner. In such metabarcoding studies, scientists sample, collect and sequence DNA, so that they can compare it with existing databases and identify the source organisms.

Furthermore, as eDNA metabarcoding assessments use samples from water, often streams, located at the lowest point, one such sample usually contains not only traces of specimens that come into direct contact with water, for example, by swimming or drinking, but also collects traces of terrestrial species indirectly via rainfalls, snowmelt, groundwaters etc. 

In standard fish eDNA metabarcoding assessments, these ‘bycatch data’ are typically left aside. Yet, from a viewpoint of a more holistic biodiversity monitoring, they hold immense potential to also detect the presence of terrestrial and semi-terrestrial species in the catchment.

In their new study, reported in the open-access scholarly journal Metabarcoding and Metagenomics, German researchers from the University of Duisburg-Essen and the German Environment Agency successfully detected an astonishing quantity of the local mammals and birds native to the Saxony-Anhalt state by collecting as much as 18 litres of water from across a two-kilometre stretch along the river Mulde.

After water filtration the eDNA filter is preserved in ethanol until further processing in the lab.
Photo by Till-Hendrik Macher.

In fact, it took only one day for the team, led by Till-Hendrik Macher, PhD student in the German Federal Environmental Agency-funded GeDNA project, to collect the samples. Using metabarcoding to analyse the DNA from the samples, the researchers identified as much as 50% of the fishes, 22% of the mammal species, and 7.4% of the breeding bird species in the region. 

However, the team also concluded that while it would normally take only 10 litres of water to assess the aquatic and semi-terrestrial fauna, terrestrial species required significantly more sampling.

Unlocking data from the increasingly available fish eDNA metabarcoding information enables synergies among terrestrial and aquatic biodiversity monitoring programs, adding further important information on species diversity in space and time. 

“We thus encourage to exploit fish eDNA metabarcoding biodiversity monitoring data to inform other conservation programs,”

says lead author Till-Hendrik Macher. 

“For that purpose, however, it is essential that eDNA data is jointly stored and accessible for different biodiversity monitoring and biodiversity assessment campaigns, either at state, federal, or international level,”

concludes Florian Leese, who coordinates the project.

Original source:

Macher T-H, Schütz R, Arle J, Beermann AJ, Koschorreck J, Leese F (2021) Beyond fish eDNA metabarcoding: Field replicates disproportionately improve the detection of stream associated vertebrate species. Metabarcoding and Metagenomics 5: e66557. https://doi.org/10.3897/mbmg.5.66557

Learning more about vampire fish: first report of candiru attached to an Amazonian thorny catfish

For the first time, scientists report a vampire fish attached to the body of an Amazonian thorny catfish. Very unusually, the candirus were attached close to the lateral bone plates, rather than the gills, where they are normally found. Since the hosts were not badly harmed, and the candirus apparently derived no food benefit, scientists believe this association is commensalistic rather than parasitic. The research is published in the open-access journal Acta Ichthyologica et Piscatoria.

Guest blog post by Chiara C. F. Lubich, André R. Martins, Carlos E. C. Freitas, Lawrence E. Hurd and Flávia K. Siqueira-Souza

The Amazon River Basin is home to about 15% of all freshwater fish species known to science, and an estimated 40% yet to be named. These include some of the most bizarre fishes: the vampire fishes, locally known as candiru, members of the catfish subfamily Vandelliinae.). They survive by attaching themselves to the bodies of other fish and sucking on their blood, hence their common name. Yet, it was only recently that we found out that one candiru species, belonging to the genus Paracanthopoma, seems to be making use of its host in quite a different way.

During a sampling study of freshwater fish fauna in a lake of the Demeni River Basin, a left bank tributary of the Negro River, we found candirus attached to the surface of the body of an Amazonian species of a thorny catfish. By the end of the survey, we had observed a total of twenty candirus attached to the outside of the bodies of nine larger Doras phlyzakion, one or two per host. Very unusually, the candirus were attached close to the lateral bone plates, rather than the gills, where these fish are normally found.

Location of the study: Demeni River, left bank tributary of Negro River, Amazonas State, Brazil.

As a result of these observations, we recently published the first record of a candiru attached to the body surface of an Amazonian thorny catfish in an article in the open-access scholarly journal Acta Ichthyologica et Piscatoria.

Vampire fish have long and robust snouts, with strong dentary teeth that help them stay attached to the epidermis of their host and feed on its blood. However, when we performed a macroscopic analysis of the stomach contents of the preserved Paracanthopoma specimens, we were surprised to find no coagulated blood, nor flesh, skin or mucus. This might indicate an interaction between parasite and host that is more benign than usually attributed to vampire fish. 

Doras phlyzakion with vampire fish (Paracanthopoma sp.)  fixed into its epidermis close to the bony plates of the lateral line. Arrows: areas with reddish wounds.

We believe the association between candiru and host in this case might be commensalistic (where one organism benefits from another without harming it), rather than parasitic, because the hosts were not badly harmed, and the candiru apparently derived no food benefit. 

But what else would they seek on the back of Amazonian thorny catfish? One explanation could be that, since candirus are tiny and nearly transparent, they might be avoiding getting noticed by visual predators by riding on larger fish. Another hypothesis is that they could be using their big cousins to transport them over longer distances that they wouldn’t be able to cover themselves, eventually making it to safety or new food sources.

Research article:

Lubich CCF, Martins AR, Freitas CEC, Hurd LE, Siqueira-Souza FK (2021) A candiru, Paracanthopoma sp. (Siluriformes: Trichomycteridae), associated with a thorny catfish, Doras phlyzakion (Siluriformes: Doradidae), in a tributary of the middle Rio Negro, Brazilian Amazon. Acta Ichthyologica et Piscatoria 51(3): 241-244. https://doi.org/10.3897/aiep.51.e64324