Giant pandas kept in captivity may suffer a sort of ‘jet lag’ when housed in zoos at different latitudes from their home turf.
Like humans, animals have an internal circadian clock which is synchronised to their external environment and linked to their behaviour and physiology.
Researchers from the University of Stirling in the UK wanted to find out how living at different latitudes affected giant panda activity and behaviour, publishing their findings in Frontiers in Psychology.
The results might be significant for the Adelaide Zoo (located at 34.9oS), which is currently negotiating to retain or replace its two giant pandas Wang Wang and Fu Ni, the only giant pandas in Australia.
In the wild, the historic natural range for giant pandas (Ailuropoda melanoleuca) in China covers the latitude range of 26 – 42oN.
Giant pandas live highly seasonal lives, preferring to eat certain species of bamboo, particularly their shoots the study says. The arrival of bamboo shoots in spring triggers migration, as well as breeding, probably because it’s easier to find other pandas when they are all chasing after the same food source.
But when the animals are housed in zoos – in locations outside their home latitudes – they are exposed to different environmental cues like daylight and temperature.
“When giant pandas are housed at higher latitudes — meaning they experience more extreme seasons than they evolved with — this changes their levels of general activity and abnormal behavior,” says lead author Kristine Gandia.
The researchers monitored 11 giant pandas at 6 zoos inside and outside the animal’s normal latitudinal range. They watched the pandas’ activity and behaviour over 24 hours, once a month over a 12 month period. Specific zoos in the study are not identified.
Gandia tells Cosmos “we found that pandas synchronize their activity to external cues like light and temperature”.
Daylight and temperature were important cues for pandas kept in captivity in latitudes matching their home habitat in China, the study finds. In those cases, pandas generally showed 3 bursts of activity over 24 hours, similar to their wild counterparts.
Pandas kept in zoos at different latitudes were less active, which the researchers suggest may be due to different environmental cues. Importantly, fluctuations in sexual activity could relate to the lack of environmental cues for migration.
The researchers note all pandas in the study showed some abnormal behaviours likely linked to zoo-specific cues like keepers visiting with food.
Gandia says zoos can use the approach of systematically monitoring animal behaviour, taking temperature and lighting cues into account, and trying to match husbandry practices to the pandas’ natural rhythms. “For example, providing food at times they would normally want to feed in the wild and in the portions they would consume.”
“Zoos can also use this approach and information to conduct further research to address questions at the forefront of captive animal welfare on whether/how species should be housed outside of their natural climatic and latitudinal conditions,” Gandia says.