Premium
Physiological constraints on range expansion of the invasive, air‐breathing suckermouth armored catfish (Family: Loricariidae)
Author(s) -
Fosha Kathryn Rose,
Burggren Warren W
Publication year - 2012
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.26.1_supplement.886.18
Subject(s) - loricariidae , salinity , limiting , brackish water , zoology , biology , hypoxia (environmental) , catfish , acclimatization , humidifiers , fish <actinopterygii> , fishery , ecology , chemistry , environmental science , oxygen , mechanical engineering , organic chemistry , environmental engineering , engineering
Members of the family Loricariidae, such as Hypostomus and Pterygoplichthys , are facultative air breathers and highly invasive in many North American freshwater and brackish systems. Despite management issues, little is known of their biological limiting factors and physiological ability to acclimate in new environments. Thus, environmental tolerances to temperature (10 – 38°C), salinity (0.5 – 37 ‰), and hypoxia (<21 – 2 kPa) were acutely evaluated. As temperatures were increased or decreased by 1°C day −1 , starting at 25°C, fish fed normally between 18 and 38°C (9.4 – 11.5 g, n=6). Loss of equilibrium (LOE) occurred at a critical thermal minimum of 11.3 ± 0.6°C, but the higher temperatures were well tolerated. Both species (9.3 – 11.8 g, n=12) survived salinities up to 9.8 ‰ for 7 days (168 h), with little aerial breathing and no mortality. More frequent aerial breaths were seen in 18.7 ± 1.04 ‰, until LOE occurred after 130 ± 35 min. Fish introduced to seawater (35.2 ± 1.8 ‰) quickly lost equilibrium after 17.5 ± 7.7 min of exposure. Initial hypoxia tolerance tests on 1.5 – 2 g fish (n=6) determined that LOE occurred at approximately 2.6 ± 0.3 kPa in an average of 60.0 ± 10.7 min, without access to air. These wide tolerance ranges show that temperature, salinity and hypoxia levels found in southern North America do not strongly limit range expansion of invasive Loricariids. Research supported by NSF IOS‐1025823.