---
title: "What the sources say about the Pacific Oyster | AnimalTracks.wiki"
description: "41 claims from the Pacific Oyster profile, each beside the words of the source that backs it."
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canonical: "https://animaltracks.wiki/animals/pacific-oyster/sources/"
---

# What the sources say about the Pacific Oyster (*Magallana gigas*)

> 41 claims from the Pacific Oyster profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Pacific Oyster](https://animaltracks.wiki/animals/pacific-oyster/)

## Pacific Oyster. NOAA Fisheries.

https://www.fisheries.noaa.gov/species/pacific-oyster

| The page says | The source says |
| :--- | :--- |
| A stay-put oyster that starts life male, hears underwater sound and filters up to 50 gallons of seawater a day. | an adult Pacific oyster can filter up to 50 gallons of seawater per day (note: tagline; the male start and the hearing have their own claims) |
| Filter feeder that lives on plankton | Pacific oysters can grow quickly, depending on plankton (food) availability and water quality conditions. (note: stats.diet; filter feeding has its own claim) |
| Filter feeder that lives on plankton | They are filter feeders, cleaning the water as they eat (note: stats.diet) |
| Filters up to 50 gallons of seawater a day | an adult Pacific oyster can filter up to 50 gallons of seawater per day (note: stats.superpower) |
| That is what "sessile" means. | Adult oysters are sessile—they stay in one place. |
| stays in one place for life once it settles | they will grow their own shells and can live for the rest of their lives |
| Male oysters release their sperm by clapping their shells together, often when the water is warm and coming in with the tide. | Male oysters release their sperm by clapping their shells together, often when the water is warm and coming in with the tide. |
| In their first year of life, Pacific oysters are male. | In their first year of life, Pacific oysters are male. |
| As they get older, some develop female reproductive organs while their male organs shrink. | As they get older, some will change and develop female reproductive organs, while their male organs shrink. |
| A female can release anywhere from 50 to 200 million eggs in a spawning event. | a female Pacific oyster can release anywhere from 50 to 200 million eggs into the water. This is called a spawning event. |
| The tiny larvae drift in the upper layers of the water. | The tiny oyster larvae develop in the upper layers of the water and drift with the currents |
| After about 20 to 22 days they settle on a shell, rock or other suitable surface, grow their own shells and can live there for the rest of their lives. | After about 20 to 22 days, the oysters are ready to settle down on the bottom of the bay. They attach themselves to a shell, rock, or other suitable surface, where they will grow their own shells and can live for the rest of their lives. |
| NOAA says a Pacific oyster can reach 10 to 12 inches. | reaching up to 10-12 inches |
| Its shell is long, thick and rough, and sometimes sharp around the edges. | Their shells—known as valves—are naturally long, thick, rough, and sometimes sharp around the edges. |
| One of the two valves is cupped, which is why the animal is also called the Pacific cupped oyster. The other valve is flat. | One of the two shells is cupped, which is why they are also called "Pacific cupped oysters," while the other is flat. |
| Valves are the two halves of the shell. | they have a hinged shell with two parts (note: valves; NOAA: shells known as valves) |
| Oysters are filter feeders. | They are filter feeders, cleaning the water as they eat |
| An adult can filter up to 50 gallons of seawater a day, and that filtering improves light penetration for underwater plants. | an adult Pacific oyster can filter up to 50 gallons of seawater per day. This filtering of the water improves light penetration for submerged aquatic vegetation to thrive. |
| Oysters can also form reefs that give critical habitat to many species, including fish and invertebrates like the native Olympia oyster. | Oysters can also form reefs providing critical habitat for many species including fish and other invertebrates like the native Olympia oyster. |
| It lives in intertidal and subtidal areas | They inhabit both intertidal and subtidal areas. |
| The Washington State Department of Fisheries introduced it from Japan in the 1920s, and it is now a popular aquaculture species on the US West Coast. | The Pacific oyster, introduced from Japan in the 1920’s by the Washington State Department of Fisheries, is now a popular West Coast aquaculture species (note: West Coast in a NOAA (US agency) page is the US West Coast; NOAA Region: Alaska, West Coast) |
| NOAA Fisheries gives a length of up to 12 inches | Length Up to 12 inches (note: faq 1; replaces SeaLifeBase 45 cm max (FAO 1998 via Ref. 348), which disagrees with NOAA's page updated 04/13/2026. School-ruler comparison is a 12-inch ruler, needs no claim) |
| NOAA Fisheries lists both Crassostrea gigas and Magallana gigas for the species, which it also calls the Japanese oyster, Miyagi oyster and Pacific cupped oyster. | Crassostrea gigas; Magallana gigas Also Known As Japanese oyster, Miyagi oyster, Pacific cupped oyster |
| Male first, maybe female later | In their first year of life, Pacific oysters are male. (note: heading) |

## Magallana gigas summary page. SeaLifeBase.

https://www.sealifebase.se/summary/Magallana-gigas.html

| The page says | The source says |
| :--- | :--- |
| Shallow brackish and coastal waters of the northwest Pacific, from Hong Kong to Kamchatka; introduced across the rest of the Pacific, Atlantic and Indian Oceans and the Mediterranean | Northwest Pacific: from Hong Kong, east to Taiwan, and north to Kamchatka, Russia. Introduced in the rest of the Pacific, Atlantic, Indian Ocean and the Mediterranean. (note: stats.habitat) |
| Shallow brackish and coastal waters | Benthic; brackish; depth range 0 - 15 m (note: stats.habitat) |
| Not Evaluated | IUCN Red List Status (Ref. 130435 : Version 2025-2 (Global)) Not Evaluated (note: stats.conservationStatus. No Red List assessment exists for Magallana gigas or Crassostrea gigas (GBIF has no category, Crossref no assessment DOI), so no IUCN reference is cited. SeaLifeBase prints the same status.) |
| The species is native to the northwest Pacific, from Hong Kong east to Taiwan and north to Kamchatka, Russia. | Northwest Pacific: from Hong Kong, east to Taiwan, and north to Kamchatka, Russia. |
| SeaLifeBase lists it as introduced across the rest of the Pacific, the Atlantic, the Indian Ocean and the Mediterranean. | Introduced in the rest of the Pacific, Atlantic, Indian Ocean and the Mediterranean. |
| SeaLifeBase gives a depth range of 0 to 15 meters and a temperature range of 15 to 30 degrees Celsius. | depth range 0 - 15 m (Ref. 348 ). Subtropical; 15°C - 30°C |

## Crassostrea gigas. AnAge: The Animal Ageing and Longevity Database.

https://genomics.senescence.info/species/entry.php?species=Crassostrea_gigas

| The page says | The source says |
| :--- | :--- |
| AnAge lists a maximum of 7 years in the wild. | Maximum longevity 7 years (wild) |
| The longest AnAge records in the wild is 7 years, and it rates that figure as resting on a small sample. | Maximum longevity 7 years (wild) Source ref. 1307 Sample size Small (note: faq 2) |

## Charifi et al. (2017). The sense of hearing in the Pacific oyster, Magallana gigas. PLOS ONE.

https://doi.org/10.1371/journal.pone.0185353

| The page says | The source says |
| :--- | :--- |
| oysters briefly shut their valves when they were played loud enough sounds from 10 hertz to just under 1,000 hertz | At high enough acoustic energy, oysters transiently closed their valves in response to frequencies in the range of 10 to <1000 Hz |
| Their sensitivity peaked between 10 and 200 hertz. | with maximum sensitivity from 10 to 200 Hz |
| five oysters with shells 70 to 75 millimeters long weighed 72 grams on average | The analysis was performed on 5 oysters (shell length 70–75 mm, weight 72.4 ± 10.7 g (note: 72.4 g is the stated mean (m ± sd), sd 10.7; scoped to the five test oysters) |
| in a lab test, oysters briefly shut their valves to loud enough sounds from 10 hertz to just under 1,000 hertz | At high enough acoustic energy, oysters transiently closed their valves in response to frequencies in the range of 10 to <1000 Hz (note: vibe.reason) |
| their sensitivity peaked between 10 and 200 hertz | with maximum sensitivity from 10 to 200 Hz (note: vibe.reason) |

## Charifi et al. (2018). Noise pollution limits metal bioaccumulation and growth rate in a filter feeder, the Pacific oyster Magallana gigas. PLOS ONE.

https://doi.org/10.1371/journal.pone.0194174

| The page says | The source says |
| :--- | :--- |
| In a 14-day test with cadmium, a metal pollutant, in the water, oysters exposed to cargo ship noise grew 2.6 times slower than oysters that heard no ship noise. | Four oyster-groups were studied during a 14-day exposure period. ... Oysters exposed to Cd in the presence of cargo ship-noise accumulated 2.5 times less Cd in their gills than did the controls without ship noise and their growth rate was 2.6 times slower. (note: Cd is cadmium; the abstract names it as the metal in the water) |
| They also stayed shut more during the day. | In the presence of ship noise, oysters were closed more during the daytime |
| An oyster that can hear a cargo ship | Shipping has increased dramatically in recent decades and oysters can hear them. (note: heading) |
| Yet it can hear. | Shipping has increased dramatically in recent decades and oysters can hear them. |