Anthropogenic effects on Mountain Chickadees Breeding in Urban Ecosystems.

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Urban landscapes can pose both challenges and benefits to birds. Artificial lighting, altered vegetation, and differences in microclimate between urban and native habitats can affect timing and success of breeding, while noise pollution associated with urban landscapes can impede communication and increase stress levels. Introduced predators, such as cats, often occur at much higher densities than native predators in rural sites. However, food supplementation from bird feeders can increase individual overwinter survival/condition of urban birds, and nest boxes can increase availability of nesting substrate. The ability to compensate for the relative advantages vs disadvantages of urban settings may depend on plasticity of affected species, and many urban-exploiters are habitat generalists. It is therefore surprising that mountain chickadees (Poecile gambeli) - montane conifer forests specialists - do well in urban landscapes.    Our mountain chickadee studies in Kamloops, BC have found birds breeding in urban areas: start breeding up to two weeks earlier; have nestlings with higher feather growth rates; are more likely to double brood; and, have higher song output during dawn singing - a trait known to reflect a male's physical condition in chickadees. Urban mountain chickadees appear to compensate for noise pollution via both use of modified songs and calls which reduce known signal-jamming aspects of urban noise on chickadee vocalizations. The research we will undertake investigates the interaction between relative food availability, microclimatic variation and noise/light pollution in urban vs rural landscapes, and how these interact with mountain chickadee condition, settlement and nesting phenology.    We will install Light and Temperature Data Loggers on nest boxes distributed throughout multiple urban, rural and interface sites around Kamloops, BC, and manipulate relative food quality available during the winter at different sites. We will couple these with tracking relative insect prey-availability and monitor noise pollution using Autonomous Recording Units (ARU) mounted on nest trees. We will then monitor nest initiation, reproductive output and double-brooding between rural and urban sites to determine which anthropogenic effects most influence nesting phenology and success. We will track individual condition of males with respect to a bird's habitat and manipulated variation in winter/spring food availability via dawn singing behaviour. Leg-band embedded PIT tags placed on nestlings will allow us to track dispersal and survival of nestlings using a network of up to 200 Radio-Frequency Identification(RFID)-equipped bird feeders set across southern Kamloops. The integration of demographic studies and behavioural research will provide insight into what renders anthropogenic landscapes exploitable, which provides guidance for urban planning that integrate these features for avian conservation into our cities.