Marine Animals Survey

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Marine Animals Survey
Survey Sequence and Effective Years (All years are fiscal years)	data	Result list (Japanese only except )
5th survey 1998-2003		Report of the survey on Marine animal Report of the survey on Marine animal Report of the survey on Marine animal (Pinnipedia, Sea otters) Report of the survey on Marine animal (Finless Porpoises) Report of the survey on Marine animal (Sea Turtles)

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1. Survey Objectives

The objective is to conduct a survey on the current distribution, breeding status and habitat of sea turtles, Pinnipedia , whales and other large marine animals living in coastal region of Japan, and thereby compile basic data for protecting the coastal environment serving as the habitat of species targeted in the survey.

2. Survey Content and Methods

Existing information required for each survey was collected, and the habitat survey techniques were studied.

For sea turtles, existing data was collected and field surveys and environmental surveys were conducted with respect to sand beaches where sea turtles land and lay eggs in Japan (Caretta caretta, Chelonia mydas and Eretmochelys imbricata).

For whales, the survey targeted Neophocaena phocaenoidees (phocoenidae family) which do not migrate and are deemed to be vulnerable to changes in the coastal environment, from among marine animals which live in coastal region of Japan. To estimate their population, a watching survey from aircraft was conducted in principal areas of distribution.

For Pinnipedia, a survey was conducted with respect to the landing count and the population of Phoca vitulina, Phoca largha, Histriophoca fasciata and Eumetopias jubatus in the eastern region on Hokkaido. For Enhydra lutris, information on their visits was collected through habitat surveys and interview surveys.

3. Survey Results

<Sea turtles>
There are 844 sand beaches in 30 prefectures nationwide, where sea turtles landing and laying eggs have been recorded in the past. Among them, sea turtles were confirmed to have landed on 567 sand beaches within five years prior to the survey years (1998 and 1999) (Some records are overlapping, as more than one species landed on the same sand beach.). A table was prepared, showing the number of turtles which landed, the number of turtles which laid eggs, and the hatching status in sand beaches across the nation. Furthermore, a distribution map of sea turtles was produced, based on a topographical map on a scale of 1:25,000. Additionally, a list of organizations conducting surveys and implementing conservation activities for sea turtles was prepared.

The results of the surveys conducted in 1998 and 1999 were analyzed in detail, and the breeding status of sea turtles in shallow waters and the conditions of the neritic environment were summarized. Also, based on literature data, challenges in conserving the neritic ecosystem were defined, with sea turtles serving as indicators.

<Whales>
To estimate the population, a watching survey from aircraft was conducted in principal areas of distribution in Japan. The current population of Neophocaena phocaenoidees in each coastal areas was determined thereby.

<Pinnipedia and Enhydra Lutris>
The causes of the rapid increase in the landing population of Phoca vitulina living in the eastern part of Hokkaido since 1997 were revealed, and the population in Cape Erimo was found to be genetically different from the population in other regions by genetic analysis. Also, the head count of Phoca largha and Histriophoca fasciata, which are predominant species in the southern parts of the Sea of Okhotsk during the sea-ice season, was estimated. Both species were found to be living in Shiretoko Peninsula, in high density.