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Urban light pollution linked to smaller eyes in birds
The northern cardinal's eyes were five per cent smaller if they lived in the city.
Birds living in cities had smaller eyes than those on outskirts.

A study has suggested that the lights in cities may have resulted in some birds evolving to have smaller eyes.

The researchers, from Washington State University, discovered that some birds living year round in the urban setting of San Antonio, Texas, had eyes that were smaller than those in the less bright outskirts.

The investigation involved them studying more than 500 birds from central and edge areas of San Antonio, a major city in Texas. The researchers compared the body and eye sizes of the birds, and analysed noise and light measurements during night and day in each area.

Two songbird species, the northern cardinal and the Carolina wren, had eyes that were five per cent smaller if they lived year-round in the city, compared to members of the same species in the outskirts.

However they found no eye-size difference between the two species of migratory bird, the painting bunting and the white-eyed vireo, no matter where in the city they predominantly lived.

This may suggest that residential birds are adapting to the brighter lights of urban areas, while the time migratory birds stay away from these places means that they have not. This could make it challenging when they return to these areas to breed.

Developing smaller eyes over time may be helping the birds to deal with the brighter, constant light of city environments, whereas birds with larger eyes could be somewhat blinded or struggle to sleep.

This is the first known study to show a connection between eye size and a bird’s ability to cope with sensory pollutants as part of city life.

Todd Jones, the study’s first author, said: “Humans may have some unintended consequences on birds that we don’t realise,

“We don’t know if these adaptations could have good or bad consequences for the birds down the road, considering that urban environments aren’t going away anytime soon. It is also important to understand how to manage such environments for the birds that maybe aren't urban adapted.”

The full study can be found in the journal Global Change Biology.

Image © Shutterstock

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Webinar to explore history of KC breed registers

News Story 1
 A free webinar exploring the development of the Kennel Club's registration system and the evolution of closed breed registers has been announced.

Hosted by Dr Alison Skipper, veterinary and research advisor at the Kennel Club, the webinar will delve into the development of the registry and how the changing landscape of scientific knowledge has shaped breeding practices. It will also look at what this means for the future of pedigree dogs.

The session will culminate with a look at The Kennel Club's ongoing and future engagement in this area, with a chance for attendees to put forward their thoughts and questions for discussion.

This event takes place on Microsoft Teams on Tuesday, 10 June at 7pm. To learn more, visit events.teams.microsoft.com  

Click here for more...
News Shorts
UK's BSE risk status downgraded

The WOAH has downgraded the UK's international risk status for BSE to 'negligible'.

Defra says that the UK's improved risk status recognises the reputation for having the highest standards for biosecurity. It adds that it demonstrates decades of rigorous animal control.

Outbreaks of Bovine Spongiform Encephalopathy, also known as mad cow disease, have previously resulted in bans on Britain's beef exports.

The UK's new status could lead to expanded trade and better confidence in British beef.

Christine Middlemiss, the UK's chief veterinary officer, said: "WOAH's recognition of the UK as negligible risk for BSE is a significant milestone and is a testament to the UK's strong biosecurity measures and the hard work and vigilance of farmers and livestock keepers across the country who have all played their part in managing the spread of this disease.