News

The IUCN Red List of Threatened Species has just published its second update of the year (28th October 2024), including reassessments for hundreds of small mammal species submitted by the Small Mammal Specialist Group (SMSG). Unfortunately, the most significant changes concern a worsening in Red List categories. Read more about some of these assessments below. 

Admiralty Rat (Rattus detentus) – Critically Endangered (Possibly Extinct)

Formally described only as recently as 2016 from Manus Island of Papua New Guinea, this species has only ever been recorded a handful of times. Unfortunately, hope for this species is slim, as multiple surveys undertaken between 1962 and 2014 have failed to record it. Local hunters in 2014 considered it too rare to be worth hunting, and targeted surveys and ethnographic questionnaires since then have failed to find evidence of the species. It is possible that is has already disappeared.

Applying the IUCN’s recommended extinction assessment framework, we estimated the probability that the species is extinct to be 0.76. The Admiralty Rat now joins the 15 other rodent species that are already listed as Possibly Extinct.

Bahaman Hutia (Geocapromys ingrahami) – Critically Endangered

Populations of this hutia have already been extirpated from parts of the Bahamas due to a hunting, predation by dogs and possibly cats, and competition with other invasive mammals. This species is now only thought to occur on three cays, though persistence on one of these is uncertain.

Since this species has such a small, restricted distribution, it is only found in a few locations, and there is ongoing decline, it has reached the status of Critically Endangered. A Species Action Plan which considers future reintroduction options is urgently needed.

Heath Mouse (Pseudomys shortridgei) – Endangered 

The Heath Mouse is found in parts of South and Western Australia, where lack of success in targeted surveying has raised cause for concern. It’s thought that climate change, wildfires, habitat loss and degradation, as well as predation by cats and foxes, have been driving a decline in numbers. Now, based on its small area of occupancy, low number of locations, and continuing decline, this species is Endangered.

Seram Orange Melomys (Melomys fulgens) – Vulnerable 

This species – previously unrecorded since 1920 and assessed as Data Deficient – was recently documented as surviving on the island of Seram in Indonesia, in research led by SMSG Deputy Chair for Conservation Actions, Prof. Sam Turvey.

Whilst this “rediscovery” is incredibly promising for the species, its recent Red List assessment highlights that we must take action to continue survey work. It has been listed as Vulnerable based on its small distribution and threats to its lowland forest habitat (logging and agriculture).

Western European Hedgehog (Erinaceus europaeus) – Near Threatened

A well-recognised and widely-loved small mammal, the Western European Hedgehog is nowadays facing a multitude of threats. Roads, agricultural intensification and urban growth have likely affected populations across its range. With evidence indicating local and national declines thar are approaching, and in some areas, exceeding 30% over a decade, this hedgehog has been moved from the category of Least Concern to Near Threatened.

Have you ever heard of a muskrat island? On the rocky Isles of Shoals in Maine and New Hampshire, in an environment that should, in theory, be poorly matched to muskrats, these rodents are thriving.

Undergraduate researcher Max Zeltsar, supervised by our Deputy Chair for Eulipotyphla, Dr Alexis Mychajliw, has been studying these island populations to help us understand how they are surviving. Hear more from Max about his project, below:

Hello, my name is Max Zeltsar and I am a student and undergraduate researcher at Middlebury College in Vermont. Over this past summer, I have been working in collaboration with the Shoals Marine Laboratory and my advisor, Dr. Alexis Mychajliw (Middlebury College), to study an incredibly unique population of muskrats (Ondatra zibethicus) that live on the Isles of Shoals in Maine and New Hampshire. While most people remember these islands for the many gulls and seals that call them home, us mammalogists affectionately call them the “muskrat islands” on account of the successful muskrat population.

Muskrats were introduced to the islands sometime between the late 1800s and early 1900s. Currently, there is no documentation explaining why they were introduced, but given the timing, it is possible that humans brought them to the islands to supplement the fur trade. Regardless of the reason for the introduction, muskrats have thrived on the Isles of Shoals since their arrival to the archipelago.

The ongoing survival of these muskrats raises many interesting questions about our understanding of the species. Muskrats are semi-aquatic mammals and inhabit wetland and stream ecosystems. While they can live in saline and freshwater environments, they are reliant on aquatic plants, a network of permanent or longstanding waterways, and soft workable mud for shelter, food, and safety. The Isles of Shoals are primarily composed of rocky coastal zones and patches of scrub brush and exposed grass. Freshwater sources are largely driven by the presence of rain and most large bodies of water can dry up within a couple of days. Although most of their traditional predators don’t live on the islands, gulls that inhabit the islands during their breeding season will predate muskrats as well as chase them away from their nesting sites. In other words, the Isles of Shoals should be virtually uninhabitable for muskrats and yet they continue to survive in remarkably high densities.

Despite how incredible and bizarre the ongoing presence of muskrats on Shoals is, there has been very little research to understand their ecology. The goal of my research is to understand how muskrats are surviving on the Isles of Shoals. By answering questions about their habitat selection, behaviour, and diet we can understand what may or may not be limiting their populations. Investigating these topics required a range of approaches. From June to August, an 8-week-long camera trap survey was implemented to observe their distribution and study their activity patterns. Scat transects were also used to monitor changes in activity and to understand what environmental factors (e.g. ground cover, exposure, presence of territorial gulls) influenced the density of that activity. Lastly, stable isotope analysis is being conducted to understand what the muskrats are consuming and how flexible their diets may be.Through a combination of these various techniques, we can gain a deeper understanding of the ecology of Shoals muskrats. Given their status as an introduced species, it is particularly important to understand how these muskrats are interacting with the Shoals ecosystem. The Isles of Shoals provide important nesting habitat for many globally important species of seabirds and learning how muskrats may or may not be impacting that habitat is essential for proper management and conservation. Furthermore, learning how muskrats are living on the Isles of Shoals can contribute to our broader understanding of the species. Muskrats are declining across their endemic range and their traditional wetland habitat is becoming increasingly threatened by anthropogenic development. Studying how muskrats are surviving on the Shoals archipelago could contribute to broader conservation efforts and help us understand how adaptable or resilient the species may be. Lastly, this research contributes to the theory of island biogeography and our concept of what happens genetically, morphologically, and behaviourally to various species and taxa when they become isolated. Whilst this population of muskrats may seem like a very specific research topic, the knowledge that can be gained from them has the potential to be incredibly far-reaching. In other words, the Shoals muskrats are small mammals with big impacts!

Max’s project is funded by the Middlebury College Undergraduate Research Office. Find out more about small mammal research in the HEDGE lab here: https://insectivora.org/our-research/, and the Shoals Marine Lab here: https://www.shoalsmarinelaboratory.org/

Thank you to Dan Bowen who joined our SMSG team on a summer internship! Dan has recently completed his placement, during which he focused on bringing a number of Japanese endemic small mammal Red List assessments up to date. We were delighted to have Dan working on spiny rats, moles, shrews and more! Hear from Dan, below:

“I’m Dan and I undertook an internship with the IUCN Small Mammal Specialist Group drafting Red List reassessments for some Japanese endemic species. I grew up in Shropshire, attending state schools and volunteering at my local wildlife trust in my spare time. Despite being from a working-class background, I worked hard and made it to the University of Oxford. I am studying Biology, and am on my final year doing my Masters in Biology research project, which I hope will support me in my career in ecology and conservation.

At university, I have been very fortunate to have access to a wide range of internship opportunities, including this one with the IUCN SMSG. My internship involved performing literature research for Japanese endemic species, researching if there had been any changes in distribution or population trends. If so, I would add this new information to the current species distribution map and update the running species information sheet, preparing the drafts for review by species experts.

During my internship, I have learned new insights into conservation and developed my researching skills. I have a better understanding of the process behind the IUCN Red List system, and a greater appreciation for the work that goes on behind the scenes in ensuring this information is available to the public.

I wanted to say thanks to the IUCN SMSG, and especially my supervisors Abi and Ros, who have all been very welcoming and supportive throughout my internship. I look forward to see the work I have been performing with the group contribute to the current understanding we have around these rare species.”

A Tokudaia (spiny rat) species. Source: Daderot, Wiki.

Alpenzoo (Austria) is the 19th conservation organisation to establish a Centre for Species Survival in collaboration with the IUCN Species Survival Commission (SSC), the world’s largest volunteer conservation-science network.  

Five of the nineteen Centres recognised globally by the SSC are based in Europe. Alpenzoo is proud to announce the establishment of a new Centre for Species Survival, which will significantly enhance their commitment to the conservation of small mammal taxa.

Centres for Species Survival are partnerships between conservation organisations and the SSC – a Commission made up of more than 10,000 species conservation experts worldwide. Centres are hosted by leading zoological, botanical and aquarium conservation organizations that are actively focused on key species or specific geographical regions.

Within this collaboration, Alpenzoo will be teaming up with the IUCN SSC Small Mammal Specialist Group (SMSG) to assess risk of extinction within this animal group and help speed up the planning and implementation of conservation action. The first step will be the establishment of a Programme Officer based at Alpenzoo, working remotely within the Specialist Group.

Co-Chair Ros Kennerley

“The IUCN SSC Small Mammal Specialist Group is delighted to be part of this exciting new partnership, which aims to bolster conservation efforts for the world’s 3,200+ small mammals. We look forward to growing our team with Alpenzoo and working with them to assess species for both the IUCN Red List of Threatened Species and Green Status and support conservation planning for species and multi-species planning in key regions.

Having a dedicated member of staff based at Alpenzoo will make a huge difference to what the SMSG can achieve for small mammals, which are generally under-researched and over-looked in terms of conservation funding and activities. It is brilliant to have Alpenzoo on board and we hope to see other institutions within the zoo community also step up to assist small mammal conservation.”

Dr Ros Kennerley, Co-Chair of the IUCN SSC Small Mammal Specialist Group, based at Durrell Wildlife Conservation Trust.

The SMSG represents a global network of scientists and conservationists who share a passion for the world’s often overlooked and under-studied rodents, shrews, moles, solenodons, hedgehogs and treeshrews. The Group serves as the Red List Authority for these taxa, but also works to promote conservation actions on the ground and develop strategies to enable more effective projects for small mammals. Alpenzoo has long been interested in small mammal work, having developed a breeding programme for the Bavarian pine vole (Microtus bavaricus). The vole is now being transferred to other zoos, with a few specimens also being released into the wild for the first time this year.

André presenting to EAZA 2023 on the SMSG

“Our new Centre for Species Survival in collaboration with the SSC marks a significant milestone, as it is an honor to become the 19th zoo worldwide to initiate such a vital program. CSS Alpenzoo will play a crucial role in providing scientific insights, assessing extinction risk, and expediting the planning and implementation of conservation action. Our mission is to ensure the survival of highly threatened species across the globe, and we are already witnessing promising outcomes. For instance, our conservation project for the Bavarian pine vole has achieved groundbreaking success taking place right here at the Alpenzoo.

We are committed to continuing our efforts to protect and preserve biodiversity. This new Centre will enable us to contribute even more effectively to global conservation initiatives, ensuring a brighter future for many threatened species.”

Dr André Stadler, Alpenzoo Director.

Alpenzoo is unique in that it exclusively houses Alpine species native to the region. Visitors are treated to stunning views of Innsbruck and the surrounding mountains while exploring a habitat that includes over 2,000 individuals across 150 animal species typical of the Alps. As the only zoo globally dedicated to Alpine wildlife, it has achieved considerable success. The zoo is actively involved in reintroduction initiatives for various species, including wild cats (Felis silvestris), bearded vultures (Gypaetus barbatus), black vultures (Aegypius monachus), European pond turtles (Emys orbicularis), and Northern Bald Ibis (Geronticus eremita).. Notably, it has conducted annual ibex (Capra ibex) releases for over 20 years and is planning on releasing a variety of different animals in the future. Through the new Centre for Species Survival, Alpenzoo will further increase their focus on small mammal taxa across a range of outputs, from coordinating global-level Red List and Green Status assessments, to promoting small mammal work within the zoo itself.

“We are excited to have Alpen Zoo join the global network of Center for Species Survival partnerships which now spans 13 countries and 6 continents. Together these leading conservation institutions have hired almost 50 highly-qualified staff working in support of priority species conservation science and action. Through joint efforts like these we can secure a thriving future for the species we share this planet with.”

Dr Kira Mileham, IUCN SSC Strategic Partnership Director.

Official launch of the Alpenzoo CSS. Photo credit: Thomas Steinlechner

Texas A&M University is pleased to continue their involvement with the Small Mammal Specialist Group (SMSG) through the appointment of new members Maria Alejandra Hurtado Materon, a PhD student in Ecology and Evolutionary Biology Program, and Dr Michelle Lawing, Associate Professor at Texas A&M in the Department of Ecology and Conservation Biology. They will work closely with Emeritus Professor Thomas Lacher (Co-Chair of the SMSG), as he will serve as advisor to the team while they focus on coordinating the next round of Red Listing for small mammals in the Americas.

Find out more about Michelle and Maria below:

Michelle and Maria

Maria Alejandra Hurtado Materon is a Ph.D. student in the Interdisciplinary Ph.D. program in Ecology and Evolutionary Biology at Texas A&M University. Her research focuses on the ecological and evolutionary processes that drive current and historical biodiversity patterns. She uses an integrative approach that combines functional traits, biogeography, phylogenetic comparative methods, and modeling techniques. Additionally, she is developing a periodic table of niches for mammals. Since Spring 2024, Maria has been working as a research assistant in the TAMU-Red List Partnership.

A. Michelle Lawing is an Associate Professor in the Department of Ecology and Conservation Biology (lawinglab.org). Her research is focused on how biodiversity responds to climate and environmental change and her approach involves interdisciplinary work at the nexus of conservation biology, ecology, evolution, and paleontology. She is particularly interested in functional traits of mammals and reptiles and how they are aligned with environments in the Anthropocene, Late Pleistocene, and throughout the Miocene to present.

The Texas A&M team will be involving undergraduate students in Red List assessing and drafting species updates before seeking input from species experts. Equally, this work will spread awareness of the Red List process and help to build new skills earlier in the training process of the conservation workforce. Undergraduate students at Texas A&M will have the opportunity to participate in assessments by joining a year-long Aggie Research Program and becoming certified Red List and Green Status assessors.

Maria Alejandra and the Texas A&M team have also been working to develop an R script to assist assessors in the mapping stages. This script includes tools for occurrence cleaning, map modification, and the calculation of AOO (Area of Occupancy) and EOO (Extent of Occurrence) metrics in accordance with IUCN requirements. Moreover, there are plans to explore a broader assessment process; we have started to work on select Green Status assessments through the help of the SMSG’s current intern, Salomé.

The SMSG is thrilled to have the Texas A&M team in place and look forward to bringing you more assessment updates.

The SMSG would like to say a huge Thank You to Erin McDonald for her work on a number of Red List reassessments for small mammals. Erin joined the team in the UK for a 6 month part-time internship through Durrell.

Erin McDonald

“During my six-month internship with the IUCN SSC Small Mammal Specialist Group, I have been focusing on drafting global Red List assessments and range maps of small mammals, this included updating previously assessed species and drafting assessments for newly described species. Throughout the internship, I have gained new skills, such as GIS, and developed my knowledge of small mammal ecology and habitats. The desire to learn more about the Red List framework began following a lecture from Dr David Mallon in which I was informed about the global and regional assessor exam, after I completed this, I wanted to put the knowledge I had learnt into practice and offered my help to the SMSG. Abi and Ros guided me through the process of drafting assessments and range maps in line with IUCN guidelines. Throughout this time, I have drafted assessments for many small mammal species, from hedgehogs to shrews, which will be sent off to species experts before finalisation and uploaded to the IUCN Red List site. It will be both exciting and rewarding to see the species assessments I contributed towards published online.

I am currently studying for an MSc in Conservation Biology at Manchester Metropolitan University and this opportunity has allowed to me gain valuable skills and knowledge that I can transfer into my future conservation career as well as providing me the opportunity to build connections with experts in the industry. I am grateful to Ros and Abi for their guidance throughout my internship and for giving me such a great opportunity.”

Here are just a few of the species that Erin has worked on: