An open guide to the Peruvian sea

Two parts

The guide brings together every animal species in IMARPE's Peruvian Register of Marine Species (PeRMS), with their common names, their conservation status, the regions of the Peruvian sea where they have been recorded and what is seen at each ORKA dive site. The logbook is where our guides and contributors record each outing: which species they saw, how many, at what depth, with photos and, when possible, which individual it was.

Sources and licences

• Master list: Santamaría, J.; Romero, C.; Meza, M. (Eds.) (2025). Peruvian Register of Marine Species (PeRMS), IMARPE, in WoRMS Editorial Board (2026). World Register of Marine Species. doi:10.14284/170. Licence CC BY 4.0.
• Common names: WoRMS, Wikidata (CC0) and, where they say where a name is used in Peru, citable documents such as the Master Plan of the Mar Tropical de Grau National Reserve 2026–2031 (SERNANP). Every name shows its source; the ones marked as Peruvian are those with a Peruvian citation.
• Images: Wikimedia Commons, only under CC0, public domain, CC BY or CC BY-SA, always with the author's credit and a link to the licence. Photos by our contributors carry the licence each author chose.
• Records by region: OBIS (Ocean Biodiversity Information System) and GBIF (Global Biodiversity Information Facility), only records licensed CC0 or CC BY. See where each list comes from and the data credits.
• Conservation status: the IUCN Red List as recorded in Wikidata, open to review by our curators.
• Map: the outline of Peru and its neighbouring countries is from Natural Earth (public domain). The four regions of the sea are cut at 4.5° S, 6.0° S and 12.16° S and drawn as bands 150 km wide: they are not official boundaries, the map does not draw the exclusive economic zone or the Reserve's limits, and it does not use the ecoregions' geometry (its licence does not allow redistribution), only the two measured latitudes. Where the browser allows it, the map is drawn over an interactive basemap from OpenFreeMap (OpenMapTiles tiles), with data from © OpenStreetMap contributors (ODbL); the bands are still the same ones, drawn over the Natural Earth coastline.
• Places: the positions of the towns, ports and beaches that name the regions (Talara, Sechura, Callao, Chorrillos, Tacna…) and of the piers, coves and beaches the logbook uses to warn ‘that looks like the pier’s position’ are from OpenStreetMap, © OpenStreetMap contributors (ODbL), as are the place names and the shoreline ORKA uses to place each logbook record in its province and its stretch of coast.

Where each list comes from

The “Where?” filter on the species list offers all of Peru and four regions of the sea, from north to south:

• Tropical northern sea, from the border with Ecuador to 4.5° S (between Lobitos and Talara).
• Tropical–cold transition zone, from 4.5° S to 6.0° S (from Talara to Sechura and Bayóvar): the southern half of the tropical ecoregion, where warm-water species gradually give way to cold-water ones.
• Cold central sea, from 6.0° S to 12.16° S (from southern Piura to Lima and Callao).
• Cold southern sea, from 12.16° S to the border with Chile (from Chorrillos to Tacna).

Together they are exactly Peru's three marine ecoregions in the global MEOW system (Spalding et al. 2007, doi:10.1641/B570707): Guayaquil, which the guide splits in two, Central Peru and Humboldtian. That way each list can be compared with Reef Life Survey and with the literature. The 6.0° S and 12.16° S cuts are the boundaries of those ecoregions measured where they meet the coast (on the Illescas peninsula, and between Barranco and Chorrillos, at the foot of the Morro Solar), in two independent copies of the layer: VLIZ's and UNEP-WCMC's. The 4.5° S cut comes from Ibáñez-Erquiaga et al. 2018 (PLoS ONE 13(11):e0208244) and from the Master Plan of the Mar Tropical de Grau National Reserve 2026–2031, which place the start of the transition there. A region reaches the edge of the Peruvian sea: an offshore record counts in the region of its latitude.

A species appears on a region's list for one of these reasons, which its page states in words:

• With scientific records here: at least two records from the same source (OBIS or GBIF; they are not added together, because they share datasets) or a museum specimen, always licensed CC0 or CC BY. Fossils and, in GBIF, iNaturalist observations are left out.
• Isolated record: just one openly licensed record. It is not shown unless you choose to include species with a single record.
• Seen by ORKA: a sighting from our logbook that a curator verified and published.
• Confirmed by a curator: a curator added it with their own source.

Records under a non-commercial licence (CC BY-NC) do not count towards any public list: they remain as suggestions for a curator to decide on with their own citation. A curator can also rule out a doubtful record.

Data credits

The regional lists come from run area-lists/0a4966e43106 of our import, with the following datasets.

GBIF

GBIF.org, derived dataset: 10.15468/dd.97a5mq.

OBIS

Sensitive species

This guide shows where and when each species was seen, including threatened or protected ones — the seahorse, the spiny lobster, the sea cucumber, the turtles. Each one's page explains how to behave around it and which regulation protects it. The data we send to OBIS and GBIF, on the other hand, generalise the location of these species.

How the species accounts are made

Each species account is written from published sources and kept, in Spanish and in English, in a repository with a history of changes. Before publishing it, a program checks the whole account again, and if a single check fails the account does not go out:

• Every paragraph cites at least one source and its last sentence ends in a citation. Whatever has no source is left blank.
• Sources are consulted live at publication: every DOI is compared with Crossref or DataCite (title and year), every book with its ISBN and every link is opened. Only sites from a closed list are accepted (scientific journals, IMARPE, SERNANP, WoRMS, IUCN, OBIS, GBIF, among others). Wikipedia and iNaturalist are not sources.
• The text may not share any sequence of 8 words with Wikipedia, FishBase, SeaLifeBase or the abstract of a cited article: facts are taken with their citation, the wording is our own.
• A name is called Peruvian only if it has a Peruvian citation, and the IUCN category is that of the current global assessment, cited.
• The Spanish and English versions have the same sections, the same paragraphs, the same citations and the same figures.

Accounts go out in batches, at most 140 species a week. Each version is numbered and dated under “How to cite”, and a correction is published as a new version. If you see an error, use “Report an error” at the foot of the account.

Verifying and publishing

No logbook record becomes public unless a curator reviews it, and nobody verifies their own record. Verifying (is the identification right?) and publishing (should the world see it?) are two separate decisions.

Working with the Reserve

The 2026–2031 Master Plan of the Mar Tropical de Grau National Reserve provides for a participatory monitoring system with databases and mobile apps, and protocols for turtles and for rocky-reef fishes and invertebrates. This logbook is an independent ORKA project, designed to contribute to that system: it records in the Darwin Core standard (with individuals, depth, effort and location) so the verified data can be shared with SERNANP, IMARPE, OBIS and GBIF.

Explore the guide

By group:

• Bony fishes
• Sharks, rays and chimaeras
• Marine mammals
• Sea turtles and reptiles
• Seabirds
• Octopuses and squids
• Nudibranchs and sea slugs
• Sea snails
• Bivalves
• Chitons and other molluscs
• Crabs, lobsters and shrimps
• Other crustaceans
• Sea stars, urchins and sea cucumbers
• Corals, anemones and sea fans
• Jellyfish, hydroids and comb jellies
• Sponges
• Sea squirts and salps
• Marine worms
• Parasites
• Other animals

By region of the sea:

• Tropical northern sea
• Tropical–cold transition zone
• Cold central sea
• Cold southern sea

Protected and threatened species · Tree of marine life · Map by region