CatMap Project

The first statewide effort to map feral cat colonies in Hawaiʻi. Over 900 colonies and 6,500 sightings logged, with confidential location handling so colony managers and conservation staff could share a map without anyone burning trust to do it.

Predecessor Project
Now part of FeralMap

What CatMap did

CatMap was the first statewide attempt to put feral cat colonies and sightings onto one map that agencies, researchers, and caretakers could actually use. nene.org built it. What came out of it:

  • Over 900 mapped colonies across the main Hawaiian Islands
  • 6,500+ community sightings from 550+ contributors
  • A spatial record that fed into work on nēnē, ʻuaʻu (Hawaiian petrel), and other native species exposed to cat predation and toxoplasmosis
  • A reporting workflow that kept colony locations confidential so caretakers would participate
  • The data and the lessons that became FeralMap

How it worked

Confidential colony mapping

Exact colony locations stayed private. Density patterns were visible to anyone.

Overlap with native species

Colony and sighting data could be cross-referenced with known nēnē and seabird habitat.

Community reporting

Anyone with a phone could log a sighting. Most of the dataset came from people who do not work in conservation.

Toxoplasmosis context

Cats are the only definitive host for Toxoplasma gondii, which is the most common infectious disease diagnosed in nēnē. Knowing where cats concentrate is step one for managing that exposure.

By the numbers

CatMap totals

900+
Mapped colonies
6,500+
Sightings reported
550+
Active contributors

Most of the records came from people who do not work in wildlife conservation. That is the whole point.

Why locations stayed confidential

Colony locations are sensitive. Caretakers worry about retaliation against the animals. Conservation staff worry about nēnē nests sitting downstream of a known feeding site. Keeping exact coordinates private was what made the dataset possible at all.

Why cats matter for nēnē

Cats hit nēnē two ways. They prey on goslings directly, and they shed Toxoplasma gondii oocysts that nēnē pick up while grazing. Toxoplasmosis is the most common infectious disease diagnosed in nēnē, with 21 to 48 percent of birds tested on Kauaʻi, Maui, and Molokaʻi showing exposure. Toxoplasma also reaches Hawaiian monk seals and other native species. Mapping where cats concentrate is step one for any of that work.

From CatMap to FeralMap

FeralMap is the successor

Cats are not the only invasive species people will report if you give them a usable tool. FeralMap carries the cat workflow forward and extends it to eleven species that field staff and the public actually run into: mongoose, rats, coqui frogs, little fire ants, and others.

Lessons from CatMap

  • People will report wildlife if the form takes under a minute
  • Location privacy is the difference between participation and silence
  • A report only matters if an agency can act on it
  • One form per species. Not one form for everything.

What FeralMap adds

  • Eleven invasive species, not one
  • Routing to the right agency by species and island
  • Mongoose reports on Kauaʻi flagged for biosecurity
  • iOS app launching January 2026

Species now tracked in FeralMap

Feral animals
  • • Feral Cats (from CatMap)
  • • Feral Pigs
  • • Feral Goats
  • • Axis Deer
  • • Mongoose
Invasive pests
  • • Coqui Frogs
  • • Little Fire Ants
  • • Coconut Rhinoceros Beetles
Invasive birds
  • • Rose-ringed Parakeets
  • • Barn Owls
  • • Cattle Egrets

Beta: FeralMap is open for use right now. Full public launch is January 1, 2026. Reports submitted during beta still feed agency response.

Where CatMap data lives now

The cat sightings and colony records from CatMap moved into FeralMap, which keeps the cat workflow and adds ten other species. There is no separate CatMap site to maintain.

FeralMap displays sightings as H3 hexagons. Density is visible. Exact points are not.

Report on FeralMap

Cat sightings, colony reports, and other invasive species now go through FeralMap.

Use FeralMap

Cats and ten other invasive species get reported on FeralMap.

Beta: Public launch January 1, 2026. Reports work now.

FeralMap status

Open beta
Eleven species supported
Reporter contact info kept private

Public Launch

January 1, 2026