Effects of plant phenology and solar radiation on seasonal movement of golden takin in the Qinling Mountains, China

Abstract

The golden takin (Budorcas taxicolor bedfordi) is a large, forest-dwelling ungulate endemic to the Qinling Mountains, China. A recent study showed that golden takin move to different elevations depending on the season, remaining at high elevations in summer, intermediate elevations in winter, and at low elevations for short periods in spring and autumn. We proposed the following hypotheses: seasonal movement of golden takin is a response to a shift in vegetation phenology, which affects forage quality; and uphill movement of golden takin in winter is an adaptation to select areas with higher thermal energy. To test the 1st hypothesis we used relative phenological development derived from the normalized difference vegetation index time series to link seasonal shifts in vegetation phenology to movement patterns of golden takin. Golden takin descended to a low elevation with the greening of vegetation in early spring, ascended to a high elevation in late spring, and descended again in autumn as vegetation senesced. To test the 2nd hypothesis we compared thermal energy in the winter habitat with that in other areas of the home range, using the amount of solar radiation calculated by a solar radiation model. In winter, preference of the golden takin for exposed southern slopes at intermediate elevations correlated closely with areas of higher solar radiation. Our results indicate that solar radiation and vegetation phenology are critical factors in driving seasonal movement of golden takin.

Timing of seasonal migration in mule deer: effects of climate, plant phenology, and life-history characteristics

“…Timing of altitudinal migration of red deer and North American elk (Cervus elaphus) coincided with the phenological delay in emergent vegetation at higher elevation (Morgantini and Hudson 1989, Boyce 1991, Albon and Langvatn 1992. Multiple altitudinal movements by golden takin (Budorcas taxicolor) in China were determined by the corresponding fluctuations in plant phenology and solar radiation (Zeng et al 2010). Likewise, female mule deer departed winter range as NDVI began to increase and, thereafter, the daily probability of migration increased in response to both the absolute and daily change in NDVI (Table 2; Fig.…”

“…In strongly seasonal environments, large herbivores typically migrate between discrete ranges, which is thought to have evolved in response to the dynamic patterns of forage quality and availability (Morgantini and Hudson 1989, Albon and Langvatn 1992, Hebblewhite et al 2008, predation risk , and weather patterns (Nelson and Mech 1981, Loft et al 1989, Kucera 1992, Grovenburg et al 2009). Indeed, migrants often acquire a selective advantage through enhanced fitness (Dingle 1985, avoid resource bottlenecks by obtaining access to greater food supplies in larger and less densely inhabited ranges, and obtain forage in the most nutritious phenological stages (McCullough 1985, Albon and Langvatn 1992, Holdo et al 2009, Zeng et al 2010.…”

“…Global climate change is expected to alter the phenological patterns of life-history events for numerous taxa, including seasonal migration by vertebrates (Walther et al 2002, Forchhammer andPost 2004). Effects of winter weather and snow depth, as well as progression in plant phenology, on timing of seasonal movements by large herbivores have been well documented (Garrott et al 1987, Kucera 1992, Albon and Langvatn 1992, Sabine et al 2002, Zeng et al 2010. Therefore, we expected current weather conditions, driven by broadscale climate, to influence the timing of seasonal migrations among mule deer.…”

Effects of an earthquake on wildlife behavior: a case study of takin (Budorcas taxicolor) in Tangjiahe National Nature Reserve, China

“…In the Minshan Mountains, takin make seasonal altitudinal migrations to obtain fresh food and prepare for breeding (Zeng et al 2008(Zeng et al , 2010. Their spring movement from lower (below 1,300 m) to higher elevation (above 2,000 m) occurs during the end of April to early June (Wei et al 1991).…”

“…Increased activity would result in takin traveling longer daily distances and occupying a larger home range in the period after the earthquake (a period with significant aftershocks) when compared to their activity before the earthquake. With regard to elevation, we predicted that takin would be found at higher elevations after the earthquake because the earthquake occurred during the spring migration period, and their normal altitudinal migration, based on movement toward green alpine pastures (Zeng et al 2010), would not be altered.…”