Searching for a bit of peace and quiet despite unreliable cues: dispersal, settlement, and fitness of a top predator in multi-use forests and

FULL TITLE IS: Searching for a bit of peace and quiet despite unreliable cues: dispersal, settlement, and fitness of a top predator in multi-use forests and monitoring predator-prey dynamics in non-equilibrium ecosystems

Dispersal is a crucial information gathering stage in the life cycle of organisms, sampling the world in search of suitable sites to reproduce. Dispersal behaviours can have profound implications for demography, and hence applied species management. Many species have facultative protracted dispersal spanning an entire year or more, allowing them to gather information about opportunities over multiple seasons. However, individuals of these species can make more rapid, and potentially less-informed, decisions on where to settle and reproduce, especially in areas with vacant territories. However, the information available to dispersers may be unreliable because of seasonally changing conditions. For instance, some sites may appear attractive when visited by prospectors, but become suboptimal at later timepoints within the annual cycle through high mortality due to e. g. disturbance of breeding attempts or persecution of adults. Such temporal ecological traps can produce maladaptive habitat selection, reducing the fitness of ill-informed dispersing individuals and creating attractive demographic sinks that reduce the growth of the entire population.

The student will use unparalleled demographic monitoring and satellite tagging data to characterise the rules and implications of dispersal in the goshawk, a flagship species for rewilding in the UK. Goshawks had effectively been extirpated as a breeding species but are gradually recovering following reintroductions in the 1960s, with commercial conifer plantations acting as demographic sources, generating a surplus of juveniles that need to disperse within the more dangerous wider landscape with its potential ecological traps. Working alongside public and private sector forest managers and dedicated amateur and professional ornithologists, our student will test the hypothesis that ecological traps arise because of sharp temporal mismatches between information gathering by dispersers and subsequent deleterious events affecting demography:

- Goshawks' favoured nesting areas (closed canopy forests with low disturbance) are becoming scarcer owing to the prevailing age-structure of trees in northern UK forests. Forestry operations (felling and thinning) outside the breeding season can displace breeding pairs, and in saturated areas, alternative sites are limited.
- Illegal persecution in the vicinity of grouse moors and pheasant pens (where naive captive-reared pheasants are tempting prey) is most prevalent during nesting and post-fledging stages (adults and chicks/juveniles killed) rather than dispersal. Dispersing individuals may thus be recurrently attracted to areas of high mortality.
- Recreational outdoor activities in high amenity value forests are increasing sharply, including mountain biking, walking and running. The disturbance caused by such activities peaks during holiday periods that coincide with goshawk breeding rather than dispersal.

The student will rigorously evaluate the relative contributions of forest management, survival outside managed plantations and disturbance to the dynamics and future viability of the UK goshawk population, providing evidence to shape landscape-scale conservation policy. The project will thereby train a new scientist in state-of-the-art quantitative analytical approaches to shed light on the trade-offs that unavoidably arise between conservation and economic activities and the dynamic of a protected species in heterogeneous landscapes.