Reindeer Reproduction in a Warming World: Will it be Helped or Hindered by the Changing Climate?
Tveraa, T., Stien, A., Bardsen, B.-J. and Fauchald, P. 2013. Population densities, vegetation green-up, and plant productivity: Impacts on reproductive success and juvenile body mass in reindeer. PLoS ONE 8: 10.1371/journal.pone.0056450.
In a study designed to further explore this unsettled situation, Tveraa et al. "analyzed a 10-year dataset of satellite derived measures of vegetation green-up, population densities, calf body masses and female reproductive success in 19 reindeer (Rangifer tarandus) populations in Northern Norway." Based on their analysis, the four Norwegian researchers report that "an early onset of spring and high peak plant productivity had positive effects on calf autumn body masses and female reproductive success," and that "the quantity of food available, as determined by the onset of vegetation green-up and plant productivity over the summer, were the main drivers of body mass growth and reproductive success." Hence, they found no evidence for a negative effect of the speed of spring green-up, nor did they detect "a negative mismatch between early springs and subsequent recruitment." As such, Tveraa et al. very simply concluded that the "effects of global warming on plant productivity and onset of spring are likely to positively affect sub-Arctic reindeer."