Morphometrics of the Chinese grouse Bonasa sewerzowi

We report on the body size and mass and egg size and mass of the Chinese grouse (Bonasa sewerzowi), one of the least known grouse in the world. Although reported to be the smallest grouse in the world, not enough data have been available to substantiate this claim. We document that the Chinese grouse is, in fact, the smallest grouse in the world. It shows significant changes in body mass between the reproductive and nonreproductive season (males average 310 g in the reproductive season and 341 g in the nonreproductive season; females averaged 338 and 315 g, respectively). Egg mass averages 20.6–21.6 g and shows significant annual variation. The Chinese grouse shows some of the highest relative reproductive investment among grouse, both for egg mass (6.1–6.9% of female body mass) and clutch mass (38–43%).     

An ecological framework linking scales across space and time based on self-thinning

Scaling up from measurements made at small spatial and short temporal scales is a central challenge in the ecological and related sciences, where predictions at larger scales and over long time periods are required. It involves two quite distinct aspects: a formulation of a theoretical framework for calculating space-time averages, and an acquisition of data to support that framework. In this paper, we address the theoretical part of the question, and although our primary motivation was an understanding of carbon accounting our formulation is more general. To that end, we adopt a dynamical systems approach, and incorporate a new dynamical formulation of self-thinning. We show how to calculate rates of change for total (and average) plant dry mass, volume, and carbon, in terms of the properties of the individual plants. The results emphasize how local scale statistics (such as, variation in the size of individuals) lead to nonlinear variation at larger scales. Further, we describe how regular and stochastic disturbance can be readily incorporated into this framework. It is shown that stochastic disturbance at patch-scales, results in (to first approximation) regular disturbance at ecosystem scales, and hence can be formulated as such. We conclude that a dynamical formulation of self-thinning can be used as a generic framework for scaling ecological processes in space and time.