Study of the ascidian collection at the National Museum of Nature and Science, Tsukuba, revealed some Japanese specimens of the non-native ascidian, Ascidiella aspersa (Müller, 1776), collected in 2007 from both mid-temperate Oominato, Mutsu Bay, in the northernmost part of Honshû, and from warm-temperate Ago Bay, Kii Peninsula, middle Honshû. These specimens were collected one year earlier than the previous earliest Japanese record from cool-temperate Funka Bay, Hokkaido. Mutsu Bay has an international port, which can be assumed to be the invasion gateway for this ascidian from abroad. On the other hand, this ascidian may have arrived at Ago Bay by domestic transport because all of the bay’s ports are strictly for domestic use under governmental regulations. A comparison of the publicly available sequences for the 18S rRNA gene among this species and its allies suggested the possibility that it inhabited Korean waters as far back as the late 1990s, and it entered Japanese waters from Korea through an as yet unknown international port(s).

Submersible survey of biological communities are conducted using diving equipment and submersible instruments that are usually heavy and bulky. It also takes time to get permits to survey the inside of harbors and ports, and to prepare diving apparatus on site. Hence, it is desirable for intertidal ecologists to be able to conduct underwater surveys without the need for special diving skills and costly instruments. A portable videography apparatus has been devised for surveying biological communities on quay walls and to conduct observation at any time. It consists of a wearable underwater video camera, macrolens and collapsible kitchen shelf. Simultaneous species identification and quantitative analysis of organisms are possible with this apparatus which combines captured images from video and a measuring tape.