Data from: Associations between human non-motorized recreational activity on nest box occupation, exploratory behaviour, and breeding success in a passerine bird

Anthropomorphic activities have a large impact on ecosystems in many ways,
one of which is how animals behave. Non-motorised nature recreation is a
popular human activity of which the impacts on nature are largely unknown.
These activities, which include hiking, biking, pet walking and horseback
riding, tend to increase during the commencement of the breeding activity
for most passerine forest birds in temperate zones. We here investigated
whether variation in recreational activity associates with patterns of
nest box occupation and reproductive success in a long-term study of
personality-typed great tits (Parus major). We measured human disturbance
in the area by recording the frequency of non-motorised recreational
activities by observations. We were particularly interested in the
relationship between disturbance levels and nest box occupancy as well as
the relationship between disturbance levels of occupied nest boxes and
exploratory scores of the great tits that occupied them. We also
investigated whether reproductive characteristics such as fledging
success, clutch size, chick weight and tarsus length varied with
disturbance levels at occupied nest boxes. We did not find a relation
between nest box occupation and disturbance. Habitat quality rather than
disturbance explained the nest occupation. More exploratory individuals
occupied boxes in less disturbed areas, independent of habitat quality.
Fitness decreased with increasing disturbance independent on habitat
quality. Chicks were heavier and had longer tarsi, and clutch sizes were
bigger in less disturbed areas. In conclusion, we found breeding site
choice of great tits to be independent on human activity, although there
are clear fitness effects of human disturbance.