Researchers have found that advanced DNA technologies can get a detailed snapshot of insect diversity within a bird’s nest, showing everything from the bird’s last meal to disease-causing parasites.
“Birds’ nests are fascinating microcosms, but until now, studies have only examined the living insects that can be seen crawling and flying around the nests,” says Valerie Levesque-Beaudin, lead author on the study and a leading expert in Diptera taxonomy at the Centre for Biodiversity Genomics (CBG) at the University of Guelph (U of G).
With newer DNA-based methods, researchers can pick up traces of environmental DNA to get a snapshot of all the species in these tiny ecosystems. “The analysis of nest contents and environmental DNA, or ‘eDNA’ as it’s called, via metabarcoding helps us to gain more insight into a bird’s diet, parasites, and other factors that could impact a bird’s health and breeding success,” says Levesque-Beaudin.
For the study, published in Metabarcoding and Metagenomics, researchers collected 20 birds’ nests from the 162-hectare Arboretum at U of G. They examined the nests using DNA barcoding to identify insects to species and DNA metabarcoding to look at the entire nest ecosystem.
Organisms leave traces of DNA behind as they move through the environment, and researchers can use metabarcoding to build a comprehensive picture of life in the nest. Metabarcoding pulls all DNA traces in a bulk sample – in this case, parts of dead insects, debris, and dust from birds’ nests. This method differs from DNA barcoding, where a single specimen – an insect in this case – is DNA sequenced to identify it to species level.
The CBG team used emergence traps for a first sweep of the nest’s contents followed by a second, deeper probe using DNA metabarcoding to identify all the species encountered in the nest. Researchers passed the nests through a sieve, collecting insect remains and the dust for DNA extraction. “We not only found insects making a living in the nest, but traces of prey, parasites, and many other things,” says Levesque-Beaudin. “The most unexpected was the amount of information gained on other birds’ species whose feathers were either used for nest building or whose nests were essentially overbuilt by the nesting species.”
“This approach has the potential to revolutionize how we study bird nests as a micro-ecosystem. It unravels connections between different ecological guilds within the nest and connections of the birds with their environment, which would otherwise remain hidden,” says Dr. Bettina Thalinger, senior author of the study.
The CBG’s Associate Director of Analytics, Dr. Dirk Steinke, says the study has positive implications for bird conservation efforts. He says his students have already begun looking at American Kestrels, a threatened bird of prey, to find out if there are clues in the nest communities via metabarcoding and if DNA can help scientists determine if lack of prey or increased parasitism could be among the causes of nestling mortalities.
Galapagos finches are another species threatened by the avian vampire fly – a parasite that attacks nestlings – and treatments include pesticides. Steinke notes that one of his graduate students has begun using DNA metabarcoding in the finches’ nests to understand better the potential impact of pesticide treatment on the entire arthropod nest community.
Levesque-Beaudin V, Steinke D, Böcker M, Thalinger B (2023) Unravelling bird nest arthropod community structure using metabarcoding. Metabarcoding and Metagenomics 7: e103279. https://doi.org/10.3897/mbmg.7.103279
News piece originally published by the Centre of Biodiversity Genomics. Republished with permission.
Montane forests, known as biodiversity hotspots, are among the ecosystems facing threats from climate change. To comprehend potential impacts of climate change on birds in these forests, researchers set up automatic recorders in Yushan National Park, Taiwan, and developed an AI tool for species identification using bird sounds. Their goal is to analyze status and trends in animal activity through acoustic data.
Compared to traditional observation-based methods, passive acoustic monitoring using automatic recorders to capture wildlife sounds provides cost-effective, long-term, and systematic alternative for long-term biodiversity monitoring.
The authors deployed six recorders in Yushan National Park, Taiwan, a subtropical montane forest habitat with elevations ranging from 1,200 to 2,800 meters. From 2020 to 2021, they recorded nearly 30,000 hours of audio files with abundant biological information.
However, analyzing this vast dataset is challenging and requires more than human effort alone.
To tackle this challenge, the authors utilized deep learning technology to develop an AI tool called SILIC that can identify species by sound.
SILIC can quickly pinpoint the precise timing of each animal call within the audio files. After several optimizations, the tool is now capable of recognizing 169 species of wildlife native to Taiwan, including 137 bird species, as well as frogs, mammals, and reptiles.
In this study, authors used SILIC to extract 6,243,820 vocalizations from seven montane forest bird species with a high precision of 95%, creating the first open-access AI-analyzed species occurrence dataset available on the Global Biodiversity Information Facility. This is the first open-access dataset with species occurrence data extracted from sounds in soundscape recordings by artificial intelligence.
The Gray-chinned Minivet (left) displays a secondary non-breeding season peak (right) which is possibly related to flocking behavior. Credit: Shih-Hung Wu, Ph.D. Candidate
The dataset unveils detailed acoustic activity patterns of wildlife across both short and long temporal scales. For instance, in diel patterns, the authors identify a morning vocalization peak for all species. On an annual basis, most species exhibit a single breeding season peak; however, some, like the Gray-chinned Minivet, display a secondary non-breeding season peak, possibly related to flocking behavior.
As the monitoring projects continue, the acoustic data may help to understand changes and trends in animal behavior and population across years in a cost-effective and automated manner.
The authors anticipate that this extensive wildlife vocalization dataset will not be valuable only for the National Park’s headquarters in decision-making.
“We expect our dataset will be able to help fill the data gaps of fine-scale avian temporal activity patterns in montane forests and contribute to studies concerning the impacts of climate change on montane forest ecosystems,”
Wu S-H, Ko JC-J, Lin R-S, Tsai W-L, Chang H-W (2023) An acoustic detection dataset of birds (Aves) in montane forests using a deep learning approach. Biodiversity Data Journal 11: e97811. https://doi.org/10.3897/BDJ.11.e97811
Another year rolled by and we at Pensoft have a lot to celebrate! This year, we marked our 30th birthday, and what a ride it’s been! We thank all of you for sticking around and helping us put biodiversity science in the spotlight where it deserves to be.
The holiday season is always great fun, but for us, every biodiversity or conservation win is reason enough to celebrate. And we’ve had so many this year! We already showed you our top species for the first half of 2022. Here’s an update for the second half with the most exciting new species that we’ve published across our journals:
The elusive owl from a remote island
The Principe scops-owl (Otus bikegila) was discovered on the small island of Príncipe, just off Africa’s western coast. Its existence had been suspected since 1998, but locals said its presence on the island could be traced back to 1928.
The bird is endemic to the island of Príncipe. Furthermore, the research team behind its discovery noted that it can be found only in the remaining old-growth native forest on the island, in an area that largely remains uninhabited.
Otus is the generic name given to a group of small owls sharing a common history, commonly called scops-owls. They are found across Eurasia and Africa, and include such widespread species as the Eurasian scops-owl (Otus scops) and the African scops-owl (Otus senegalensis).
The species epithet “bikegila”, in turn, was chosen in homage of Ceciliano do Bom Jesus, nicknamed Bikegila – a former parrot harvester from Príncipe Island and now a park ranger on the island.The new species quickly became insanely popular, generating memes (a true sign of its popularity!). One website even described it as “a flying meme-generator that sounds like a newborn puppy.”
Nepenthes pudicais a carnivorous plant that grows prey-trapping contraptions underground, feeding off subterranean creatures such as worms, larvae and beetles.
It belongs to pitcher plants – a group of carnivorous plants with modified leaves (called pitfall traps or pitchers) that help them catch their prey.
Pitcher plants usually produce pitfall traps above ground at the surface of the soil or on trees. N. pudica is the first pitcher plant known to catch its prey underground.
At first, the researchers thought the deformed pitcher protruding from the soil that they saw had accidentally been buried. Only later, when they found additional pitcherless plants, did they consider the possibility that the pitchers might be buried in the soil.
Then, as one of the researchers was taking photos, he tore some moss off the base of a tree and found a handful of pitchers.
The unique plant, however, could already be under threat. As it only lives in one small area of Indonesia, scientists believe it should be classed as Critically Endangered.
In November 2021, biologist Alejandro Arteaga and his colleagues were traveling through the cloud forests of Ecuador looking for toads, when a local woman told them she had seen odd snakes slithering around a graveyard. Based on her description, the team suspected they might be ground snakes from the genus Atractus, which had never been scientifically recorded in that area of Ecuador.
Indeed, they were able to discover three new snake species living beneath graves and churches in remote towns in the Andes mountains.
The “small, cylindrical, and rather archaic-looking” snakes all belong to a group called ground snakes. In general, not a lot of people are familiar with ground snakes, as they usually remain hidden underground.
All three snakes were named in honor of institutions or people supporting the exploration and conservation of remote cloud forests in the tropics. Atractus zgap, pictured here, was named in honor of theZoological Society for the Conservation of Species and Populations (ZGAP), a program seeking to conserve unknown but highly endangered species and their natural habitats throughout the world.
However, the majority of the native habitat of these new snakes has already been destroyed. As a result of the retreating forest line, the ground snakes find themselves in the need to take refuge in spaces used by humans (both dead and alive), where they usually end up being killed on sight.
Unlike some other participants in this list, this one took a while before it was confirmed as a new species: “We did not discover that it was a new species overnight,” says Oscar Lasso-Alcalá, one of the people behind its discovery.
A. mikoljii is a new species for science, but it is not a “new species” for people who already knew it locally under the name of Pavona, Vieja, or Cupaneca in Venezuela or Pavo Real, Carabazú, Mojarra and Mojarra Negra in Colombia. Nor for the aquarium trade, where it is highly appreciated and has been known by the common name of Oscar.
Moreover, the species has been of great food importance for thousands of years for at least nine indigenous ethnic groups, and for more than 500 years to the hundreds of human communities of locals who inhabit the Orinoco River basin in Venezuela and Colombia. In the plains of Orinoco, it is considered a delicacy “due to its pleasant taste and enhanced texture”.
Oscar Lasso-Alcalá has a special relationship with this fish. “It is more than just a fish in an aquarium since it is considered a true pet,” he says.
Recently, Javier Lobon-Rovira, one of the people behind the discovery of this new gecko, told us what it was like to find this exciting new species: “That night we were tired, so we decided to have a short walk around the camp. And… there it was…! Like a ghost, this small, cryptic, and elusive gecko started showing up in every big rock boulder.”
Kolekanos spinicaudusis part of Kolekanos, a unique and iconic gecko genus that is only known from southwestern Angola.
Until this discovery, Kolekanos only had one species in the genus, known only from ~200km south of the new discovery, but that species had feathers on its tail, not spines like K. spinicaudus. Immediately, the researchers knew they were dealing with a Kolekanos… but they were astonished to see the spines.
The scientific name “spinicaudus” refers to the unique appearance of the tail of this new species.
K. spinicaudus’s home in southern Angola remains poorly explored, even as it has been considered as an important source of diversification and endemism in West Africa.
“Insects in general are so diverse and so important, yet we don’t have scientific descriptions or names for so many of them,” says Dr Kit Prendergast, from the Curtin School of Molecular and Life Sciences.
The new bee species she discovered, Leioproctus zephyris excellent proof that we still have a lot to learn about bee biodiversity.
The story behind L. zephyr’s name is quite interesting – it was named after Zephyr the Maremma dog, Dr Prendergast’s fellow companion. The researcher says Zephyr played an important role in providing emotional support during her PhD. The name also references the dog-like “snout” in the bee’s anatomy that she found rather unusual.
The bee species was in fact first collected in 1979, but it had to wait until 2022 to be officially described.
However, Dr Prendergast says its future remains uncertain, as it is highly specialised, and has a very restricted, fragmented distribution.
“The Leioproctus zephyr has a highly restricted distribution, only occurring in seven locations across the southwest WA to date, and have not been collected from their original location. They were entirely absent from residential gardens and only present at five urban bushland remnants that I surveyed, where they foraged on two plant species of Jacksonia.”
Honorable mention: Two scorpion species described by high-school citizen scientists
In 2019, California teenagers Harper Forbes and Prakrit Jain were looking at entries on the naturalist social network iNaturalist, when they noticed a mysterious scorpion that a citizen scientist had encountered near a lake in theMojave Desert. The species had remained unidentified since it was uploaded six years earlier.
The entry that they were looking at was a yet undescribed scorpion species whose name they would add to the fauna of California. Shortly after, they found another entry on iNaturalist that also appeared to be an unknown scorpion species.
The new species, Paruroctonus soda and Paruroctonus conclusus, are playa scorpions, meaning they can only be found around dry lake beds, or playas, from the deserts of Central and Southern California.
“These kids can find anything,” Dr Esposito told The Guardian. “You set them out in a landscape and they’re like: ‘Here’s every species of snake, here’s every scorpion, every butterfly,’ and it’s kind of incredible.”
Forbes and Jain were still in high school when they made their groundbreaking discoveries. Now they are in college: Forbes at the University of Arizona studying evolutionary biology and Jain at the University of California, Berkeley, for integrative biology.
A new species of owl has just been described from Príncipe Island, part of the Democratic Republic of São Tomé and Príncipe in Central Africa. Scientists were first able to confirm its presence in 2016, although suspicions of its occurrence gained traction from 1998, and testimonies from local people suggesting its existence could be traced back as far as 1928.
The new owl species was described in the open-access journal ZooKeys based on multiple lines of evidence such as morphology, plumage colour and pattern, vocalisations, and genetics. Data was gathered and processed by an international team led by Martim Melo (CIBIO and Natural History and Science Museum of the University of Porto), Bárbara Freitas (CIBIO and the Spanish National Museum of Natural Sciences) and Angelica Crottini (CIBIO).
The bird is now officially known as the Principe Scops-Owl, or Otus bikegila.
“Otus” is the generic name given to a group of small owls sharing a common history, commonly called scops-owls. They are found across Eurasia and Africa and include such widespread species as the Eurasian Scops-Owl (Otus scops) and the African Scops-Owl (Otus senegalensis).
The scientists behind the discovery further explain that the species epithet “bikegila” was chosen in homage of Ceciliano do Bom Jesus, nicknamed Bikegila – a former parrot harvester from Príncipe Island and now a ranger of its natural park.
“The discovery of the Principe Scops-Owl was only possible thanks to the local knowledge shared by Bikegila and by his unflinching efforts to solve this long-time mystery,” the researchers say. “As such, the name is also meant as an acknowledgment to all locally-based field assistants who are crucial in advancing the knowledge on the biodiversity of the world.”
In the wild, the easiest way to recognise one would be its unique call – in fact, it was one of the main clues leading to its discovery.
“Otus bikegila‘s unique call is a short “tuu” note repeated at a fast rate of about one note per second, reminiscent of insect calls. It is often emitted in duets, almost as soon as the night has fallen,” Martim Melo explains.
The entire Principe Island was extensively surveyed to determine the distribution and population size of the new species. Results, published in the journal Bird Conservation International, show that the Principe Scops-Owl is found only in the remaining old-growth native forest of Príncipe in the uninhabited southern part of the island. There, it occupies an area of about 15 km2, apparently due to a preference for lower elevations. In this small area (about four times the size of Central Park), the densities of the owl are relatively high, with the population estimated at around 1000-1500 individuals.
Nevertheless, because all individuals of the species occur in this single and very small location (of which a part will be affected in the near future by the construction of a small hydro-electric dam), researchers have proposed that the species should be classified as ‘Critically Endangered’, the highest threat level on the IUCN Red List. This recommendation must still be evaluated by the International Union for Conservation of Nature.
Monitoring the population will be essential to get more precise estimates of its size and follow its trends. For this purpose, a survey protocol relying on the deployment of automatic recording units and AI to retrieve the data from these has been designed and successfully tested.
“The discovery of a new species that is immediately evaluated as highly threatened illustrates well the current biodiversity predicament”, the researchers say. “On a positive note, the area of occurrence of the Principe Scops-Owl is fully included within the Príncipe Obô Natural Park, which will hopefully help secure its protection.”
Thisis the eighth known species of bird endemic to Príncipe, further highlighting the unusually high level of bird endemism for this island of only 139 km2.
Even though a new species of scops-owl was just described from Príncipe, genetic data indicated that the island was, surprisingly, likely the first in the Gulf of Guinea to be colonised by a species of scops-owl.
“Although it may seem odd for a bird species to remain undiscovered for science for so long on such a small island, this is by no means an isolated case when it comes to owls,” the researchers state. “For example, the Anjouan Scops-Owl was rediscovered in 1992, 106 years after its last observation, on Anjouan Island (also known as Ndzuani) in the Comoro Archipelago, and the Flores Scops-Owl was rediscovered in 1994, 98 years after the previous report.”
“The discovery of a new bird species is always an occasion to celebrate and an opportunity to reach out to the general public on the subject of biodiversity,” says Martim Melo. “In this age of human-driven extinction, a major global effort should be undertaken to document what may soon not be anymore,” he and his team state in their paper.
“Birds are likely the best studied animal group. As such, the discovery of a new bird species in the 21st century underscores both the actuality of field-based explorations aiming at describing biodiversity, and how such curiosity-driven endeavour is more likely to succeed when coupled with local ecological knowledge, the participation of keen amateur naturalists, and persistence,” they add.
They believe that this “new wave of exploration, carried out by professionals and amateurs alike”, will help rekindle the link to the natural world, which will be essential to help revert the global biodiversity crisis.
Melo M, Freitas B, Verbelen P, da Costa SR, Pereira H, Fuchs J, Sangster G, Correia MN, de Lima RF, Crottini A (2022) A new species of scops-owl (Aves, Strigiformes, Strigidae, Otus) from Príncipe Island (Gulf of Guinea, Africa) and novel insights into the systematic affinities within Otus. ZooKeys 1126: 1-54. https://doi.org/10.3897/zookeys.1126.87635
Containing specimens from different locations, sometimes spanning across centuries, museum collections can teach us a lot about how some animals are built and how we can protect them. Properly labeled, preserved specimens can show us how the environment and species distribution has changed over extended time periods. Because in many cases these collections remain largely unexplored, a revision can reveal “treasures” that were hidden in plain sight for decades.
“The collection is unique in the region in many ways: it covers a long time span, it contains a variety of species, belonging to different families and orders, and it is composed of the work of several naturalists and employees of the museum”, Osváth says. “Due to its historical background and the presence of rare species, it is considered to be one of the most important ornithological collections in Eastern Europe.”
First, the researchers examined each bird skin and the data cards documenting the identification, locality, date, sex and catalogue number. Afterwards, they checked the species identification of specimens, determining the sex and age of birds where possible. They also updated the scientific names and taxonomy of birds. In addition, they provide a map representation with new distribution data for bird species, offering valuable information on the status of the avifauna of the Carpathian basin in the 19th and 20th centuries.
Published in the open-access journal ZooKeys, this is the first time that all those specimen data are made public.
The collection includes 925 specimens, belonging to 193 species, that were collected between 1859 and 2021. Perching birds (Passeriformes) were the best represented bird order, with 487 specimens, and 93.6 % of the specimens with known data were collected from Transylvania.
By far, the most interesting specimens were the rare ones, such as specimens of Cinereous Vulture (Aegypius monachus), Eastern Imperial Eagle (Aquila heliaca), Lesser Kestrel (Falco naumanni), all collected between 1903 and 1907 from Transylvania.
With updated information on the taxonomy and morphology of birds in Transylvania, the researchers hope this new catalogue can serve as a basis for valuable ornithological studies.
Osváth G, Papp E, Benkő Z, Kovács Z (2022) The ornithological collection of the Zoological Museum of Babeș-Bolyai University, Cluj-Napoca, Romania – Part 1: the catalogue of bird skin specimens. ZooKeys 1102: 83-106.https://doi.org/10.3897/zookeys.1102.79102
Two large-scale projects funded by the EU’s LIFE tool, one of them ongoing, facilitate the import of captive-bred or recovered vultures from Spain, France and zoos and rehabilitation centres across Europe. Birds are then accommodated in special acclimatization aviaries, individually tagged and released into the wild from five release sites in Bulgaria. Using this method, a total of 153 Griffon Vultures were released between 2009 and 2020 from two adaptation aviaries in the Kotlenska Planina Special Protection Area and the Sinite Kamani Nature Park in the Eastern Balkan Mountains of Bulgaria.
After some 50 years of absence, the very first successful reproduction in the area was reported as early as 2016. Now, as of December 2020, the local population consists of more than 80 permanently present individuals, among them about 25 breeding pairs, and has already produced a total of 31-33 chicks successfully fledged into the wild.
“Why vultures of all creatures? Because they were exterminated, yet provide an amazing service for people and healthy ecosystems”, Elena Kmetova-Biro, initial project manager for the Green Balkans NGO explains.
“We have lost about a third of the vultures set free in that site, mostly due to electrocution shortly after release. The birds predominantly forage on feeding sites, where the team provides dead domestic animals collected from local owners and slaughterhouses,” the researchers say.
“We, however, consider the establishment phase of the reintroduction of Griffon Vulture in this particular site as successfully completed. The population is still dependent on conservation measures (supplementary feeding, isolation of dangerous power lines and accidental poisoning prevention), but the area of the Eastern Balkan Mountains can currently be regarded as a one of the only seven existing general areas for the species in the mainland Balkan Peninsula and one of the five which serve as population source sites”.
Original source: Kmetova–Biro E, Stoynov E, Ivanov I, Peshev H, Marin S, Bonchev L, Stoev IP, Stoyanov G, Nikolova Z, Vangelova N, Parvanov D, Grozdanov A (2021) Re-introduction of Griffon Vulture (Gyps fulvus) in the Eastern Balkan Mountains, Bulgaria – completion of the establishment phase 2010-2020. Biodiversity Data Journal 9: e66363. https://doi.org/10.3897/BDJ.9.e66363
The Saker Falcon (Falco cherrug) is a bird of prey living in plains and forest-steppes in the West and semi-desert montane plateaus and cliffs in the East. The majority of its Central and Eastern European population is migratory and spends winters in the Mediterranean, the Near East and East Africa. With its global population estimated at 6,100-14,900 breeding pairs, the species is considered endangered according to the IUCN Red List.
In Bulgaria, the Saker Falcon, considered extinct as a breeding species since the early 2000s, was recovered in 2018 with the discovery of the first active nest from its new history in Bulgaria. The nest is built by two birds that were reintroduced back in 2015 as part of the first ever Saker Falcon reintroduction programme. The results of the 5-year programme are described in detail in the open-access, peer-reviewed Biodiversity Data Journal.
Many factors contributed to the decline of the Saker Falcon in Bulgaria and globally, and most of them are human-caused. Populations lost big parts of their habitat due to changes in land use – the transition from grazing to arable crops led to the diminishing of key food sources. Other reasons include the use of poisonous baits and the accumulation of pesticides in the food chain, illegal trade of nest-poached chicks and eggs, power line electrocution, and lack of suitable nesting places.
Even after European legislation for the protection of wildlife was implemented, and regulations were issued on the use of pesticides in Bulgaria, the Saker Falcon population did not stabilise. Its endangered status further prompted joint conservation efforts between NGOs and national authorities.
As a result, a re-introduction programme for the Saker Falcon in Bulgaria was initiated in 2015, aiming to release a number of birds over a certain period of time using adaptation aviaries, or hacks. The Green Balkans Wildlife Rehabilitation and Breeding Centre (WRBC) in Stara Zagora facilitated the captive breeding of a group of Saker Falcons imported from Austria, Hungary, Germany, Slovakia and Poland by constructing ten breeding aviaries and two stock cages for juvenile falcons and equipping them with internal surveillance cameras.
Between 2015 and 2020, a total of 80 Saker Falcons – 27 females and 53 males, were released via the hacking method from four aviaries near the town of Stara Zagora. Out of them, 64 had been bred and hatched at the WRBC.
Observation records from 2018 confirmed that at least one pair of the falcons released in 2015 was currently breeding in the wild in Bulgaria. This observation proves that with the help of hacking, Sakers can survive in the wild until maturity, return to the region of their release and breed successfully. In 2020, the female bird in the breeding pair was changed with a Saker Falcon released in 2016, and the new pair bred successfully.
In 2020, the programme was restarted for another 5 years, with the aim to release 100 Saker Falcons and have six pairs breeding in the wild. This will help restore the Saker Falcon population in the southern Balkans and facilitate gene flow amongst fragmented populations from Central Europe to Kazakhstan.
Helping this iconic species successfully establish a self-sustaining population in Bulgaria has profound implications for conservation in the country – not only in terms of public awareness of species conservation, but also as an indicator of wider environmental issues.
Lazarova I, Petrov R, Andonova Y, Klisurov I, Dixon A (2021) Re-introduction of the Saker Falcon (Falco cherrug) in Bulgaria – preliminary results from the ongoing establishment phase by 2020. Biodiversity Data Journal 9: e63729. https://doi.org/10.3897/BDJ.9.e63729
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.
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
Two different kinds of Lachrymose Mountain-Tanager (Anisognathus lacrymosus) occurring in Colombia on different mountain ranges (left: Santa Marta; right: Yariguies). Their measurements and songs were as distinct as those in the group which co-occur. Therefore, they can therefore be treated as different species.
Nature is replete with examples of identifiable populations known from different continents, mountain ranges, islands or lowland regions. While, traditionally, many of these have been treated as subspecies of widely-ranging species, recent studies relying on molecular biology have shown that many former “subspecies” have in fact been isolated for millions of years, which is long enough for them to have evolved into separate species.
Being a controversial matter in taxonomy – the science of classification – the ability to tell apart different species from subspecies across faunal groups is crucial. Given limited resources for conservation, relevant authorities tend only to be concerned for threatened species, with their efforts rarely extending to subspecies.
Figuring out whether co-habiting populations belong to the same species is only as tough as testing if they can interbreed or produce fertile offspring. However, whenever distinct populations are geographically separated, it is often that taxonomists struggle to determine whether they represent different species or merely subspecies of a more widely ranging species.
British bird expert Thomas Donegan has dedicated much of his life to studying birds in South America, primarily Colombia. To address this age-long issue of “what is a species?”, he applied a variety of statistical tests, based on data derived from bird specimens and sound recordings, to measure differences across over 3000 pairwise comparisons of different variables between populations.
Having analyzed the outcomes of these tests, he developed a new universal formula for determining what can be considered as a species. His study is published in the open-access journal ZooKeys.
Essentially, the equation works by measuring differences for multiple variables between two non-co-occurring populations, and then juxtaposing them to the same results for two related populations which do occur together and evidently belong to different “good” species. If the non-co-occurring pair’s differences exceed those of the good species pair, then the former can be ranked as species. If not, they are subspecies of the same species instead.
The formula builds on existing good taxonomic practices and borrows from optimal aspects of previously proposed mathematical models proposed for assessing species in particular groups, but brought together into a single coherent structure and formula that can be applied to any taxonomic group. It is, however, presented as a benchmark rather than a hard test, to be used together with other data, such as analyses of molecular data.
Thomas hopes that his mathematical formula for species rank assessments will help eliminate some of the subjectivity, regional bias and lumper-splitter conflicts which currently pervade the discipline of taxonomy.
“If this new approach is used, then it should introduce more objectivity to taxonomic science and ultimately mean that limited conservation resources are addressed towards threatened populations which are truly distinct and most deserving of our concern,” he says.
The problem with ranking populations that do not co-occur together was first identified back in 1904. Since then, most approaches to addressing such issues have been subjective or arbitrary or rely heavily upon expert opinion or historical momentum, rather than any objectively defensible or consistent framework.
For example, the American Herring Gull and the European Herring Gull are lumped by some current taxonomic committees into the same species (Herring Gull), or are split into two species by other committees dealing with different regions, simply because relevant experts at those committees have taken different views on the issue.
“For tropical faunas, there are thousands of distinctive populations currently treated as subspecies and which are broadly ignored in conservation activities,” explains Thomas. “Yet, some of these may be of conservation concern. This new framework should help us better to identify and prioritize those situations.”
Two different kinds of Three-striped Warblers (Basileuterus tristriatus) occurring in South America (left: East Andes of Colombia; right: a recently discovered population from the San Lucas mountains of Colombia). Note the differences in plumage coloration. While somewhat differing in voice, plumage and some measurements, the couple did not diverge as much as other related warblers that actually co-occur did. These are about as close as subspecies occurring on different mountain ranges could be. However, they marginally failed the proposed new benchmark for species rank.
Donegan TM (2018) What is a species? A new universal method to measure differentiation and assess the taxonomic rank of allopatric populations, using continuous variables. ZooKeys 757: 1-67. https://doi.org/10.3897/zookeys.757.10965
Two juveniles of Shiny Cowbird, a parasitic bird that lays its eggs in the nests of other birds, were spotted in the Andean city of Quito, Ecuador, for the first time. This finding represents an altitudinal expansion of approximately 500 m.
“The Shiny Cowbird is native to the lowlands of South America but within the last 100 years, it has been expanding its distribution to higher altitudes and latitudes” says the lead author.
The bird had already been noted from high altitudes in Bolivia and Perú, and in some localities in the Ecuadorian Andes. Since 2000, Juan Manuel Carrión, co-author and director of the Zoo in Quito, recalls observing Shiny cowbirds near his home in a valley near Quito at 2,300 m above sea level (asl). However, one has never before been reported from an altitude as high as 2,800 m asl.
Moreover, the fact that the observed individuals were juveniles means that the species is already breeding in the city.
“Such a significant expansion of reproductive birds, of approximately 500 m, could be related to human disturbances, like forest fragmentation or climate change,” adds Crespo-Pérez.
The observations took place at the PUCE campus about a year ago. Two juvenile Shiny cowbirds were seen parasitizing two different pairs of Rufous-collared Sparrow, one of the most common birds in Quito. The cowbirds displayed food-begging behaviors to adult sparrows, including chasing the sparrows on the ground and chanting intensely on bushes and tree branches.
“These observations mean that the birth mother of the cowbird laid her eggs in the nests of the sparrows, who inadvertently, became the cowbird’s foster parents and incubated, fed and cared for the it as if it were its own, even though the cowbird is almost twice as big,” says Miguel Pinto, co-author and professor at Escuela Politécnica Nacional, and former postdoctoral fellow at the Smithsonian Institution.
“The sparrows were not feeding fledglings of their own species, which suggests that the Cowbird could be having some negative effect on the Sparrow, at least on their ability to reproduce,” points out Tjitte de Vries, co-author and professor at PUCE.
There are several published reports of negative effects of Cowbirds on other birds, especially on species that are already endangered or have restricted distribution ranges. Therefore, this report of an expansion of the Shiny Cowbird towards higher altitudes may be of concern, mainly for native, endemic or endangered bird species.
Crespo-Pérez V, Pinto C, Carrión J, Jarrín E R, Poveda C, de Vries T (2016) The Shiny Cowbird, Molothrus bonariensis (Gmelin, 1789) (Aves: Icteridae), at 2,800 m asl in Quito, Ecuador.Biodiversity Data Journal 4: e8184. doi: 10.3897/BDJ.4.e8184