23 August 2026

Updating IUCN status of data deficient species?

Hi all,

I’m wondering if anyone reading this might have experience with updating wildlife protections for small mammals, and if so what it would entail. I’m based in the Pacific Northwest, and here we have several small mammals that I believe would be protected by more rigorous conservation standards if the status of their populations were better understood.

During a recent revision of the Oregon Conservation Strategy (OCS) I was able to get a freshwater clam added to the Species of Greatest Conservation Need list. It seemed like the species had been overlooked in previous OCS lists, as the literature was clear on it being a regionally rare species with a high risk of extirpation connected to land development. A major component of getting it listed was simply a researcher taking interest in the species and investigating the literature enough to support the notion that addition to the list would be warranted.

Small mammals and less “charismatic” organisms seem particularly susceptible to these blind spots, and I’m wondering if there’s something we could collectively do to remedy that. Sorex bendirii almost certainly needs to have its status in the US revised, as well as its IUCN status. Microdipodops pallidus also seems like it could be a candidate particularly with mineral extraction ramping up in the region it is endemic to.

Is demonstrating inbreeding in a rare species through genomics enough to support a conservation status change or do intensive field surveys also need to be performed?

If anyone on here has dealt with these systems (particularly with IUCN) or knows of other species that seem to have been overlooked by conservation and land management agencies, I’d love to hear more about it.

Cheers,

Daniel

p.s. I was ecstatic to see this site existed! Mammal watching has become one of my favorite hobbies, it’s great to see there are others that travel to look at rodents. Never understood why birdwatching is so popular but not mammal watching.

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Daniel Krumm
Geneticist, ecologist and huge fan of mammals (particularly rodents, bats and eulipotyphlans).
Post Views: 380

2 Comments

  • 23 August 2026
    AlvaroJaramillo

    Daniel, good question. First of all, I think you mean interbreeding (hybridization) not inbreeding? But that is just an aside. I think that with most conservation systems in the world, including IUCN, you would have to have some published material or some very good public data that shows a combination of factors. These include population declines, distributional contraction, small population or range with clear risks to that population. The issue with small mammals is that there are no trend data I would assume. So the default is a small and isolated population that triggers some conservation concern. Than alone is a risk, but usually conservation listing requires a demonstrable or documented risk to that population like habitat conversion etc. In Canada an independent body of scientists and knowledgeable folks works on creating a list of candidate at risk species, once these are accepted by a second body of scientists with an official recommendation they go to the politicians who then again decide to add it to the official list of species at risk. Here is the candidate list for Canadian terrestrial mammals, a different sub group deals with marine mammals https://cosewic.ca/index.php/en/reports/candidate-wildlife-species.html#tm

  • 24 August 2026
    Jon Swenson

    I agree that this is a good question, Daniel. The IUCN evaluations are carried out by IUCN SSC (Species Survival Commission) Specialist Groups, which usually have a number of Expert Teams under them that deal with a specific group of organisms within the topic of the Specialist Group. There is a Small Mammal Specialist Group, whose website is https://small-mammals.org/. I would recommend that you contact them and see if they have considered these species or what more information they might require.

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