Research indicates that gray squirrels can outcompete red squirrels and the reason why they have pushed the red squirrel out of large parts of England is because they have better gut bacteria.
It sounds improbable but gray squirrel gut bacteria suggests that they can digest calcium from tree bark which explains by the way why they can be destructive.
But importantly, it appears that their superior gut bacteria gives grey squirrels the advantage of better general health and immunity compared to red squirrels. They also have a broader diet and are able to access a wider range of resources.
A lot of people in Britain dislike the grey squirrel. They are an invasive species from North America introduced to the UK and Ireland in the late 19th century. They outcompete red squirrels for food. They also, apparently, transmit a disease called squirrel pox virus to red squirrels but this disease does not have a lasting effect on the greys.
I can remember a former high-profile conservative politician, Heseltine, who lives in a large house because he is very rich, surrounded by woodland and lots of garden, ordering the shooting of around 400 grey squirrels.
He described it as culling them because they were damaging his trees. From my perspective, and I accept that other people have a different perspective, he is a cruel man. But I’m digressing.
The study for this finding is published in the Journal of Medical Microbiology. The study’s title is: “Significant differences in the caecal microbiota of red and gray squirrels in Britain”. The lead researcher is Lucy Hall.
They start off their summary by saying that the red squirrel populations have declined in the UK, as we know, since the introduction of gray squirrels. The aim of the study was to “profile the caecal microbiota of red and gray squirrels”. They studied squirrels that were part of a conservation programme in North Wales.
They extracted bacterial DNA from 10 red and 10 gray squirrels and “sent for 16S rRNA sequencing.”
They concluded that the samples from the red squirrels “had significantly lower bacterial diversity and they had a higher percentage of Bacilli bacteria when compared to samples from gray squirrels.”
They also concluded that “gray squirrels had a higher abundance of bacteria belonging to the families S24-7, RF39 and Rikenellaceae”.
The conclusion in their words is as follows: “Clear differences between the caecal microbiota of the two species of squirrel were identified, which could potentially impact their overall health and ability to compete for resources.”
Link to the study: https://doi.org/10.1099/jmm.0.001793
I asked Google Gemini the following: What is being done in the UK to protect the red squirrel?
Response:
The red squirrel is a beloved but endangered species in the UK. Here’s what’s being done to protect them:
- Legal Protection: Red squirrels are fully protected under the Wildlife and Countryside Act 1981. This makes it illegal to intentionally harm, disturb, or capture them, or damage their homes (dreys). Releasing grey squirrels, which are a major threat to red squirrels, is also prohibited.
- Habitat Management: Conservation organizations like the Wildlife Trusts manage woodlands to favor red squirrels. This involves creating corridors between fragmented habitats and planting trees that provide food and shelter.
- Grey Squirrel Control: In some areas, controlled culling of grey squirrels is necessary to give red squirrels a fighting chance. This is a sensitive issue, but it’s seen as a necessary measure for red squirrel survival in certain areas.
- Research and Development: Organizations like the Red Squirrel Survival Trust are researching new methods of grey squirrel control, such as fertility control. This could be a more sustainable solution in the long term.
- Raising Awareness: Public education is crucial to garner support for red squirrel conservation. People can help by learning to identify red squirrels (and distinguish them from greys), reporting sightings, and supporting conservation efforts.
These efforts offer a glimmer of hope for the red squirrel’s future, but continued conservation efforts are needed to ensure their survival in the UK.
