QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online March 2, 2006
Journal of Experimental Biology 209, 1085-1092 (2006)
Published by The Company of Biologists 2006
doi: 10.1242/jeb.02092

This Article Figures Only Full Text Full Text (PDF) Supplementary Material Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JEB Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gonzales, T. T. Articles by Ishimatsu, A. Search for Related Content PubMed PubMed Citation Articles by Gonzales, T. T. Articles by Ishimatsu, A.

Air breathing of aquatic burrow-dwelling eel goby, Odontamblyopus lacepedii (Gobiidae: Amblyopinae)

Tomas T. Gonzales^1,2,*, Masaya Katoh³ and Atsushi Ishimatsu¹

¹ Institute for East China Sea Research, Nagasaki University, Tairamachi, Nagasaki 851-2213, Japan
² Southeast Asian Fisheries Development Center, Aquaculture Department (SEAFDEC/AQD), 5021 Tigbauan, Iloilo, Philippines
³ Ishigaki Tropical Station, Seikai National Fisheries Research Institute, Fisheries Research Agency, 148-446 Fukai-Ohta, Ishigaki, Okinawa 907-0451, Japan

^* Author for correspondence (e-mail: d705144k{at}stcc.nagasaki-u.ac.jp)

Accepted 12 January 2006

Odontamblyopus lacepedii is an eel goby that inhabits both coastal waters and intertidal zones in East Asia, including Japan. The fish excavates burrows in mudflats but, unlike the sympatric amphibious mudskippers, it does not emerge but stays in the burrows filled with hypoxic water during low tide. Endoscopic observations of the field burrows demonstrated that the fish breathed air in the burrow opening; air breathing commenced 1.3 h following burrow emersion, when water P_O2 was 2.8 kPa, with an air-breathing frequency (f_AB) of 7.3±2.9 breaths h^–1 (mean ± s.d., N=5). Laboratory experiments revealed that the fish is a facultative air breather. It never breathed air in normoxic water (P_O2=20.7 kPa) but started bimodal respiration when water P_O2 was reduced to 1.0–3.1 kPa. The fish held air inside the mouth and probably used the gills as gas-exchange surfaces since no rich vascularization occurred in the mouth linings. As is known for other air-breathing fishes, f_AB increased with decreasing water P_O2. Both buccal gas volume (V_B) and inspired volume (V_I) were significantly correlated with body mass (M_b). At a given M_b, V_I was nearly always equal to V_B, implying almost complete buccal gas renewal in every breathing cycle. A temporal reduction in expired volume (V_E) was probably due to a low aerial gas exchange ratio (CO₂ elimination/O₂ uptake). Air breathing appears to have evolved in O. lacepedii as an adaptation to aquatic hypoxia in the burrows. The acquisition of the novel respiratory capacity enables this species to stay in the burrows during low tide and extends the resident time in the mudflat, thereby increasing its chances of tapping the rich resources of the area.

Key words: Gobiidae, intertidal mudflat, aquatic hypoxia, air-breathing fish

Related articles in JEB:

EEL GOBIES SURFACE FOR AIR

Kathryn Phillips
JEB 2006 209: 0. [Full Text]  

This article has been cited by other articles:

				A. Ishimatsu, Y. Yoshida, N. Itoki, T. Takeda, H. J. Lee, and J. B. Graham Mudskippers brood their eggs in air but submerge them for hatching J. Exp. Biol., November 15, 2007; 210(22): 3946 - 3954. [Abstract] [Full Text] [PDF]

				K. Phillips EEL GOBIES SURFACE FOR AIR J. Exp. Biol., March 15, 2006; 209(6): iii - iii. [Full Text] [PDF]