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238 Hand-Rearing Birds

to parental provisioning ability, yearly food availability, and the body condition of the chick and
how much fat it was able to store.

Criteria for Intervention

Chick-napping
Shearwaters nest on the ground in burrows that they excavate into soft soils such as sand, or utilize
already‐present crevices. Newell’s Shearwaters and Hawaiian Petrels nest at higher elevations in
the mountains, while Wedge‐tailed Shearwaters nest on the periphery of the island close to the
ocean. Some species such as Wedge‐taileds may also forego a burrow altogether under crowded
conditions (Whittow 1997) and place the egg in a depression or the crux of a tree root. In most
areas where these species nest, they have evolved with no, or very few, terrestrial predators and
thus do not recognize them as a threat. This also means that they are relatively naïve to people and
will often allow a person to pick them up. Additionally, once past the initial guard phase, both
parents generally leave the chick during the day to forage at sea and this can lead well‐meaning
people to mistake a perfectly healthy nestling for an orphan and pick the chick up for care. If a
chick cannot be returned to its own burrow or the area right around it, then it cannot be put back
as the adults will not be able to find the chick to feed it (Figure 14.1).

Predation
Free‐roaming dogs and cats are a problem for ground‐nesting species that evolved in the absence
of mammalian predators. With the introduction of such predators (free‐roaming and feral domes-
tic cats, free‐roaming dogs, feral pigs, rats, and mongoose) large‐scale predation events can happen
at colonies and chicks may become orphaned from these predation events.

Natural Disasters

Colonies can be located in areas that are unstable. Landslips at colony sites happen, especially
during heavy rains. Members of the public may then find chicks at the base of a cliff in the rubble
from the colony above.

Figure 14.1 Orphaned Wedge-tailed Shearwater chicks and viable egg.