The Thoroughbreds thunder down the track, neck-and-neck, on a grisly gray day. They’re about to reach the toughest of the hurdles on their steeplechase course, a water jump with a high brush fence with orange markings. Some people say the jump’s challenging because it’s so high, others because it’s so wide. But what if the real problem is much simpler? What if the horse just can’t see it well?
According to British researchers, fence color could make a significant difference in racehorses’ ability to visualize obstacles as they approach them. Coordinating jump colors with the equine range of color vision could lead to not only better performance but also better welfare and safer racing, said Martin Stevens, PhD, professor of sensory and evolutionary ecology and chair in the Centre for Ecology and Conservation at the University of Exeter, in Penryn, the U.K.
“Orange-type colors are not very visible against the rest of the fence background and environment,” Stevens said. “In contrast, other colors such as white and certain blues and fluorescent yellows are much more visible (to horses).”
Seeing Fences Through Horse Eyes
Stevens and his colleague Sarah Catherine Paul, PhD, worked with recently developed computerized models (based on previous research on equine color receptors) for quantifying and predicting how horses see. They applied those models to numerous steeplechase jumps on 11 U.K. racetracks. The scientists took photos of different fences at different times of day and in different weather conditions. They then ran these photos through their computer model to create images of how the horse sees those fences. Later, they tested the behavior and performance of 14 racehorses jumping over different-colored jumps.
They found that orange provided low contrast, whereas white, fluorescent yellow, and bright blue provided higher contrast, Stevens said. When lighting is poor, such as on a gray day, white and bright blue offer the best contrast against the ground, and fluorescent yellow seems best against the middle of the fence.
They also noted significant differences in the way horses jumped over different-colored fences, with changes in the total jumping shape (curve) and total distance jumped. For example, horses started their jump farther back when jumping a bright blue-marked fence compared to an orange-marked fence, he said. It’s difficult to interpret all the results from this part of the experiment due to a general lack of scientific agreement about ideal jump angles and curves and what deviations mean, said Stevens. Furthermore, the horses’ different past jumping experiences could have affected their reactions. However, what’s important to note is the colors did affect the way horses jumped over them, confirming they do notice a difference and react to it, he said.
Easy Changes for Safety and Welfare
If racecourses replaced orange with white, fluorescent yellow, or bright blue, depending on the position of the marker, it’s possible both performance and injury rates would change, said Stevens. However, in the meantime, trainers should continue to work their horses over jumps of all colors to help prepare them for approaching less visible fences during an event, he added.
“I really hope that the findings lead to changes,” Stevens said. “It’s clear that the current design of U.K. courses does not cater to horse vision and that this may be improved, and the changes should not involve major challenges. Having a better understanding of how horses can see and respond to their environment has the potential to lead to a variety of changes to make the environment in which we keep them and work with them more suited to their behavior and welfare. Hopefully in time these changes will occur.”