Variable Oystercatcher

The Variable Oystercatcher, torea pango in Maori, is a robust coastal shorebird endemic to New Zealand, named for the unusual variability in its plumage, which ranges across a spectrum from entirely sooty black to a strongly pied pattern with a white belly and breast patch, with many intermediate forms in between. All morphs share the same long, straight, laterally flattened orange-red bill and sturdy pink legs typical of oystercatchers.

It is most often seen singly or in pairs patrolling sandy beaches, rocky shorelines, and estuary flats, probing and hammering for shellfish and other invertebrates with its powerful bill. Pairs are strongly territorial along stretches of coastline and can be quite vocal and aggressive in defending nesting areas from intruders.

Key field marks

• Long, straight, laterally flattened orange-red bill
• Sturdy pink legs
• Plumage variable from all-black to pied (white belly and breast patch with black head, back, and wings)
• Red eye-ring and reddish-orange eye
• Stocky, heavy-bodied shorebird shape

Similar species

• South Island Pied Oystercatcher always shows the pied pattern (never the all-black form) and is generally slimmer-billed and found more often inland during breeding, unlike the Variable Oystercatcher's strictly coastal habits.
• All-black morphs of the Variable Oystercatcher can resemble the (Australian-breeding) Sooty Oystercatcher but that species does not occur in New Zealand, so an all-black oystercatcher on New Zealand coasts is safely identified as this species.

Range

Endemic to New Zealand, breeding around the coastlines of the North Island, South Island, and Stewart Island/Rakiura.

Habitat

Strictly coastal, using sandy beaches, rocky shore platforms, shell banks, and estuarine mudflats for both feeding and nesting.

Migration

Mostly sedentary, with local movements between breeding territories and post-breeding flocking sites, sometimes gathering at favored estuaries outside the nesting season.

Behavior

Usually encountered singly, in pairs, or small loose groups, walking and probing along the shoreline; pairs defend nesting territories vigorously, chasing off intruding birds with loud calls and aggressive displays.

Voice

A loud, piercing "kleep" or "peep" call, often repeated in alarm or territorial disputes, along with softer contact notes between pair members.

Feeding

Uses its strong bill to pry open or hammer through the shells of mussels, cockles, and other shellfish, as well as probing sand and mud for worms and other invertebrates.

Nesting

Nests in a simple scrape on sand, shell, or shingle above the high-tide line, often with little added lining; both parents incubate the two to three eggs and defend the nest and chicks aggressively from predators and intruders.