Sparrow raiders show their sweet tooth
There’s no calorie counting for sparrows when it comes to quaffing the sugar they steal from cafes.
Waikato University student Mike Davy has found sparrows can tell the difference between an orange packet of raw sugar and a blue packet of low-calorie sweetener on a cafe table.
The flying sugar fiends simply don’t touch the low octane version, preferring their fix at full strength. It’s among the findings in the 22-year-old animal behaviour student’s first-ever study on the behaviour of sparrows undertaken at Momento Cafe on the university grounds.
‘‘The raw sugar has plenty of calories, so they may have chosen that because they needed the energy. Also, raw sugar is quite grainy so they could pick it up really easily. Whereas the other option is a powder and likely to be more difficult to pick up,’’ Davy said.
Davy spent 10 weeks studying the common birds from 7am-11am every weekday. In that time he noted that the sparrows stole 418 packets of sugar over 100 observation hours which equates to around four packets an hour.
The packets of sugar cost 5 cents each, which means that a cafe could see the sparrows steal around $400 worth of sugar a year. Davy also noticed that 69 per cent of the birds stealing were male compared to the 31 per cent of females.
‘‘They are eating it, I have seen them pick up the grains of sugar go over to the chicks and directly feed them sugar.’’
As it takes the birds quite a lot of effort to open the packet they tend to do it when the easier option of food scraps aren’t around. The sparrows also stay close to their energy source and distribute the sugar packets within 200 metres of the cafe. The sparrow gang also keeps regular rosters with Thursdays the biggest day for sugar theft.
Davy has turned the study into a master’s thesis and hopes that by studying the novel foraging behaviour it may help understand how wild animals can adapt to living in human-modified environments. He plans on extending the study to other cafes in Hamilton and even around New Zealand.