Guide

Look closerMammals

River otter latrines and slides

November to March

River otters live along Massachusetts ponds, rivers and wetlands all year, and their scat piles and muddy bank slides are easier to find than the animals. Look for a patch of scat packed with fish scales at a bank, log or dock edge.

Why this time of year

Otters stay active through the cold months and keep hunting where water stays open, so their signs keep appearing along the same banks.

How to notice it

  1. Walk the edge of a pond, slow river or beaver wetland and scan low banks, big logs, rocks, docks and beaver lodges for a spot where scat has piled up in the same place.
  2. Look from a step or two away at the scat. Otter scat is packed with fish scales and bits of bone, and may hold crayfish shell. It often smells fishy.
  3. Look for a smooth slide, about 6 to 10 inches wide, running down a muddy or snowy bank into the water. Check beside it for tracks, which sometimes show webbing between the toes.
  4. Leave everything where it is and note whether the same spot gets reused on a later visit.

Try this with kids: Can you find the otter bathroom? Look for a spot where scat full of fish scales is piled up, and then find the slide the otters might use to get back in the water.

Word to know: A “latrine” is a spot where otters leave scat in the same place again and again, as a message to other otters.

Safety

  • Do not touch scat or slides with bare hands, and wash hands after the outing.
  • Keep dogs from rolling in or eating scat.
  • Stay off pond and river ice and keep back from soft, crumbly banks.
  • Otters can bite if cornered; observe from a distance.

Sources

  • web.archive.orgMassWildlife 'Living with Wildlife: River Otters in Massachusetts' (Wayback copy; mass.gov 403 to fetch): otters in MA lakes, rivers, coastal habitats; remain active in winter using holes in ice; slide down snow-covered and muddy hillsides; diet fish with crayfish, frogs; use beaver bank dens, log jams, abandoned beaver lodges. Nothing on latrines.
  • web.archive.orgMassWildlife 'Learn about river otters' (Wayback copy): winter activity, sliding on muddy and snowy hillsides, crayfish in diet.
  • publications.mgcafe.uky.eduUKY Extension FOR-173: otter scat packed with fish scales, crayfish exoskeletons, bones; found along waterways, on logs, in communal latrines; slides often 6-10 inches wide; docks and piers used as latrines; fish more accessible in colder months.
  • extapps.dec.ny.govNYS DEC Conservationist 2013: active year-round; belly slides down muddy or snowy bank; bits of shells or scales sometimes the only evidence.
  • northernwoodlands.orgNorthern Woodlands 2020: otter toilet is piles of scales mixed with fecal matter, smelling strongly of fish; next to open water.
  • portal.ct.govCT DEEP: otters active all year, generally nocturnal or crepuscular; slides used repeatedly.

Checked against these sources on October 6, 2026.

In the guide for November, December, January, February, March

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