Animals within social groups respond to costs and benefits of sociality by adjusting the proportion of time they spend in close proximity to other individuals in the group (cohesion). Variation in cohesion between individuals, in turn, shapes important group‐level processes such as subgroup formation and fission–fusion dynamics. Although critical to animal sociality, a comprehensive understanding of the factors influencing coh...

A programme of research is introduced on the effects on stream ecosystems of land‐use change from native forest to pasture, and subsequent re‐afforestation with exotic pine plantations. The results detailed in the 11 accompanying papers conclude that land‐use change has had strong effects on many key physical, chemical, and biological aspects of stream ecosystems in and adjacent to Whatawhata Research Centre, near Hamilton, Ne...

The effects of shade on periphyton and invertebrates were investigated by comparisons in 12 replicate channels beside a pasture stream where shade cloth reduced the photosynthetically available radiation (PAR) by 0, 60, 90, and 98%. Periphytic productivity decreased with increasing shade. Periphyton chlorophyll a was consistently low ( −2 ) under 98 and 90% shade and usually low at 60% shade, whereas blooms were common during...

Water quality, habitat, and biota were compared during spring amongst c. 100 m reaches on 11 streams draining pasture, native (podocarp‐broadleaf) forest, and exotic pine forest established on pasture 15 years previously. Differences were greatest between the pasture and native forest streams. Only 1–3% of incident light reached native and pine forest streams whereas 30% reached pasture streams. Pasture streams had 2.2°C highe...