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Environmental variation influences food abundance and availability, which is reflected in the reproductive success of top predators. We examined maternal expenditure, offspring mass and condition for Weddell seals in 2 years when individuals exhibited marked differences in these traits. For females weighing 355 kg there was a positive relationship between maternal post-partum mass (MPPM) and lactation length, but below this there was no relationship, suggesting that heavier females were able to increase lactation length but lighter females were restricted to a minimum lactation period of 33 days. Overall, females were heavier in 2002, but in 2003 shorter females were lighter than similar-sized females in 2002 suggesting that the effects of environmental variability on foraging success and condition are more pronounced in smaller individuals. There was no relationship between MPPM and pup birth mass, indicating pre-partum investment did not differ between years. However, there was a positive relationship between MPPM and pup mass gain. Mass and energy transfer efficiency were 10.2 and 5.4% higher in 2002 than 2003, which suggests costs associated with a putatively poor-resource year were delayed until lactation. Heavier females lost a higher proportion of mass during lactation in both years, so smaller females may not have been able to provide more to their offspring to wean a pup of similar size to larger females. MPPM had only a small influence on total body lipid; therefore, regardless of mass, females had the same relative body composition. Females with male pups lost a higher percentage of lipid than those with female pups, but by the end of lactation female pups had 4.5% higher lipid content than males. It appears that for Weddell seals the consequences of environmentally induced variation in food availability are manifested in differences in maternal mass and expenditure during lactation. These differences translate to changes in pup mass and condition at wean

Penguins are often considered to be as ecologically and behaviourally homogenous as their morphology. Their structural morphology and associated physiological adaptations are governed by the demands of operating as flightless, subsurface marine predators. However, within the very strict constraints of this lifeform, penguins show considerable ecological and behavioural heterogeneity, although some of this undoubtedly relates to the range of latitudes and biotopes in which penguins breed. In this paper we: (i) briefly summarise and review some of the main features of the breeding biology, ecology and demography of penguins; (ii) identify consistent patterns across species in the grouping of these features – and highlight anomalies; (iii) suggest explanations/hypotheses for some of the potential links between ecology, behaviour and demography within these groupings; (iv) investigate six topics containing potential paradoxes, namely: migration, fasting, mate fidelity, brood reduction, demography and duration of breeding seasons. We conclude that in many biological and ecological traits penguins can be divided into two groups: (i) resident species, feeding inshore with short fasts ashore, breeding at an early age and having low divorce rates, and; (ii) migrant species, feeding offshore with long fasts ashore, breeding at older ages and having higher divorce rates. The placement of Magellanic Spheniscus magellanicus and Gentoo Pygoscelis papua Penguins in opposite groups to their congeners is particularly intriguing. We suggest that trade-offs between the year-round abundance and predictability of prey and the latitudinally-influenced time available for breeding are important determinants of these patterns. Considerably improved basic biological and ecological data on penguins and careful testing of explicit hypotheses will be required to investigate further both the suggested patterns and the remaining paradoxes.

The University of Maryland (UMD) is one of the BAA contractors performing research on aerial image understanding for the RADIUS project. UMD is contributing model-based and context-based change detection (CD) and monitoring algorithms. The principal accomplishments for this third annual report are the following: (1) improvements to detecting and counting of vehicles on parking lots as well as along roads; (2) monitoring vehicle formations, such as convoys and railroad cars, and (3) integrating the vehicle detector within the RCDE platform. UMD used geometric and context information derived from site models to accomplish these tasks.

We present a vision system for the 3D model-based tracking of unconstrained human movement. Using image sequences acquired simultaneously from multiple views, we recover the 3D body pose at each time instant without the use of markers. The pose-recovery problem is formulated as a search problem and entails finding the pose parameters of a graphical human model whose synthesized appearance is most similar to the actual appearance of the real human in the multi-view images. The models used for this purpose are acquired from the images. We use a decomposition approach and a best-first technique to search through the high dimensional pose parameter space. A robust variant of chamfer matching is used as a fast similarity measure between synthesized and real edge images. We present initial tracking results from a large new Humans-In-Action (HIA) database containing more than 2500 frames in each of four orthogonal views. The four image streams are synchronized. They contain subjects involved in a variety of activities, of various degrees of complexity, ranging from simple one-person hand waving to two-person close interaction in the Argentine tango.