The naturalization of invasive alien species. Gymnocoronis spilanthoides DC. (Asteraceae) in Kochi City, Kochi Prefecture is first described in detail. The patches of this species known as Senegal tea plant were found in the Shinkawa River and its two tributaries, the Kitayama and the Taiyou Rivers. The area covered by them in each stream was estimated to be 4495㎡, respectively, Although small patches developed in shade, well-grown patches frequently occurred in various depth and water velocity regardless of particle size of the sediment under sunny conditions.

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The laridiid bird Little Tern Sterna albifrons sinensis is one of the vulnerable animals designated by the Ministry of the Environment. Information on breeding colonies of this bird on Shikoku Island is given here for the first time. The occurrence of 22 colonies was comfirmed from 1970 to 2011, though ten of them disappeared from the area. Accoding to the colony size recorded from 2005 to 2011, I estimated the number of bred pairs to be 670. Most colonies were found on bank and mouth of rivers and on reclaimed lands. The number of pairs in large flocks on the river mouth and reclaimed land usually decreased in a short time. Frequent occurrence of re-colonization and disappearance of this bird seemed to be related with unstable environmental factors affecting their successful breeding in this area.

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The authors studied sex ratio and annual fluctuation of wintering population of the Daurian Redstart Phoenicurus auroreus (Passeriformes, Turdidae) in Kochi Prefecture, Japan. A total of 1179 birds was recorded from 1999 to 2011. Number of birds recorded from Takasu-Otsu area in Kochi City, and from mountainous Sanrei area in Kami district showed a considerable year-by-year fluctuation from 2001 through 2011. Extremely low counts in Sanrei area in some years probably related with low air temperature observed in this area. Males were significantly fewer than females, with an average sex ratio being discussed.

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The usage of artificial roosts by the Ussurian tube-nosed bat Murina ussuriensis was studied in the Shikoku Mountains from June 2011 to November 2012. This species has been known to use dead leaves as roosts in autumn. In this study the following items were used as artificial roosts; leaves of Mallotus japonicus , Macleaya cordata and Pelasites japonicus, hemp sack, and two kinds of paper trap. Bats were recorded 58 times from May to November 2012, and 21 individuals were released with a tag for identification. Frequent usages of the artificial roosts by bats were confirmed in autumn. Most results of this study agreed with those in previous reports from Kyushu, Japan.

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A chiropteran fauna was studied in and near five artificial caves and tunnels in Kami and Kochi Cities, central Kochi Prefecture, Japan. A total of 2754 individuals in the following six species were recorded from December 2010 to March 2013: Rhinolophus ferrumequinum, Rhinolophus cornutus, Myotis macrodactylus, Miniopterus fuliginosus, Murina hilgendoffi, and Murina ussuriensis. Although there was not enough evidence to proof the breeding, seasonal occurrence of the species suggested that these roosts were important to complete their life cycle including migration to larger hibernating sites.

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The gray bunting Emberiza variabilis of the bird family Emberizidae has been known as a winter visitor in Kochi Prefecture on Shikoku Island. This species was observed 13 times on Mt. Sanrei in late spring to mid-summer from 2001 to 2009. In June 2009 four eggs laid in a nest were found in Sasa nipponica community on Mt. Sanrei at an altitude of about 1450m, representing the first breeding record of this bird in Kochi Prefecture.

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