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The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

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Common name: dwarf hawkfish

Synonyms and Other Names: spotted hawkfish, falco hawkfish, boar hawkfish

Taxonomy: available through www.itis.gov

Identification: Cirrhitichthys falco is a small species of hawkfish characterized by numerous short filaments (cirri) at the tip of its 10 dorsal spines. It has thickened and elongate pectoral fin rays that allow it to perch on coral branches (Myers 1999). The cirri are white with red membrane tips on the dorsal spines (Randall 2005). The body is white with small red to dark brown spots grouped to form triangular bars, the darkest centered below the dorsal fin origin; two narrow red bars extending ventrally from the eye; and a median dark reddish band on the head (Randall 2005).

Size: This species reaches 7 cm total length (Myers 1999).

Native Range: Cirrhitichthys falco is found in the Western Pacific from southern Japan to the Great Barrier Reef, New South Wales, and New Caledonia; east to the islands of Micronesia and Samoa Islands; and west to the Maldives (Randall 2005).

Interactive maps: Point Distribution Maps

Ecology: Cirrhitichthys falco commonly inhabits areas of rich coral growth on reefs at depths of 4-46 m (Myers 1999). This species prefers Pocillopora (stony coral) colonies even when the coral is in low abundance (Coker et al. 2015). The common name hawkfish is derived from their habit of perching on the branches of coral or other structures which offer them protection against predators and a strategic point for hunting prey (Myers 1999). The primary diet consists of small benthic invertebrates including crustaceans, mollusks, and annelids; the with smaller juveniles prefer copepods and adults show preference for decapods (Kadota et al. 2011a). Courtship and spawning occur at dusk during the warmer months (Myers 1999). Cirrhitichthys falco is protogynous, starting life female and changing into a male (Myers 1999). Males of this species maintain home ranges that include the territory of 2-3 females (Kadota et al. 2011a). When the dominant male disappears, the largest female transforms into a male and assumes the territory (Kadota et al. 2011b). Interestingly, this species has bi-directional sex change driven by social context, whereby if the females in a territory disappear the male can transform back to a female to maintain reproductive opportunities (Kadota et al. 2011b).

Means of Introduction: Possible hitchhiker, recorded from a dry dock at Pearl Harbor, Oahu that had been transported from Guam (Mundy 2005).

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

References: (click for full references)

Coker, D.J., A.S. Hoey, S.K. Wilson, M. Depczyuski, N.A.J. Graham, J-P.A. Hobbs, T.H. Holmes, and M.S. Pratchett. 2015. Habitat selectivity and reliance on live corals for Indo-Pacific hawkfishes (Family: Cirrhitidae). PLoS ONE 10(11): e0138136.

Kadota, T., J. Osato, H. Hashimoto, and Y. Sakai. 2011a. Harem structure and female territoriality in the dwarf hawkfish Cirrhitichthys falco (Cirrhitidae). Environmental Biology of Fishes 92:79-88.

Kadota, T., J. Osato, K. Nagata, and Y. Sakai. 2011b. Reversed sex change in the haremic protogynous hawkfish Cirrhitichthys falco in natural conditions. Ethology 118: 226-234.

Mundy, B. C. 2005. Checklist of Fishes of the Hawaiian Archipelago. Bishop Museum Bulletins in Zoology, Number 6.

Myers, R.F. 1999. Micronesian reef fishes: A field guide for divers and aquarists. Coral Graphics, Guam.

Randall, J.E. 2005. Reef and shore fishes of the South Pacific. University of Hawaii Press, Honolulu, Hawaii, USA.

Other Resources:

Author: Brown, ME

Peer Review Date: 1/1/1900

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.