Haematopus unicolor
Silhouette: terngirl · PhyloPic
In 3 days ~60% in a week ~90%
The variable oystercatcher (Haematopus unicolor) is a species of wader in the family Haematopodidae. It is endemic to New Zealand. The Māori name is tōrea-pango. They are also known as 'red bills'. "Variable" refers to the frontal plumage, which ranges from pied through mottled to all black. They are polymorphic meaning they have different genetic variants. These color differences are attributed to the latitude of the habitat, where the northernmost oystercatchers have significantly more white on their bodies than those of southern origin. All Stewart Island variable oystercatchers are black. They have pink legs, an orange eye ring and orange-red beaks. Similar to a needle in shape, the bill is thin and long, and darkens to a deep red color during the breeding season. Males are around 678 grams and females slightly larger at around 724 grams. Length of individuals range from 42 to 47 cm from beak to tail and have a short, sturdy body with a thick neck.
Variables can be identified as they are slightly larger than the South Island pied oystercatcher (SIPO are around 550 grams). Occasionally completely black, but if they are pied (black and white) they can be easily confused... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Rakiura National Park | 🇳🇿 New Zealand | |
| 2 | Abel Tasman National Park | 🇳🇿 New Zealand | |
| 3 | Fiordland National Park | 🇳🇿 New Zealand | |
| 4 | Egmont National Park | 🇳🇿 New Zealand |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Auckland | 🇳🇿 New Zealand |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Ōtorohanga Kiwi House | 🇳🇿 New Zealand |
Possible
About 30% of wildlife watchers report a VOC sighting in Auckland on a given day, based on 1,848 verified sightings from GBIF citizen-science data. It is the 26th most-seen of the 93 birds we can rate there. Over three days the chance rises to about 60%, and over a week to about 90%, if each day is a fresh chance.
March and December
In those months about 40% of wildlife watchers report a VOC in Auckland on a given day, against about 20% in April–May and August–September, the lowest months.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most VOC sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Auckland, in our data
Auckland is the only city on Wallace's Line with enough records to rate VOC sightings: about 30% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the VOC is recorded against all the birds logged in Auckland (1,848 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
