Table 1 Summary of studies addressing the sudden appearance and/or disappearance of nudibranchs in intertidal areas
References | Species | Location | Observation dates | Emersion | Main findings on population fluctuation |
|---|---|---|---|---|---|
[36] | Chromodoris zebra | Fairyland Creek and Millbrook Creek, Bermuda | June–August of 1913–1914, Aug 1915–Oct 1916, Jan 1917 | Not mentioned | Diurnal shoreward movement in response to physical conditions (e.g. positive phototropism) |
[4] | Doris bilamellata | Wimereux, France | August of 1922 | Not mentioned | Appearance and disappearance in the intertidal area related to spawning migrations and subsequent adult death after spawning |
[9] | Embletonia fuscata | Barnegat Bay, USA | Nov 1928, Jun to Sep 1929 | Not mentioned | Fluctuations due to the fortuitous settlement and rapid development of larvae in the intertidal zone, which were brought by waves and currents. Post-spawning disappearance related to mortality by food scarcity and/or environmental factors such as low temperature |
[7] | 22 species (**) | Monterey Bay, USA | Nov 1934 to May 1935, Jul to Aug 1936 | Not mentioned (tide pools) | Fluctuations due to fortuitous larval settlement in the intertidal zone, which were brought by currents and waves |
[27] | 30 species (****) | The Netherlands | Not specified | Lamellidoris bilamellata Emerged to forage | N/A |
[10] | 24 species (***) | Isle of Man, UK | Oct 1955 to Jun 1958 | Acteonia senestra in exposed rocks | Fluctuations due to fortuitous larval settlement in the intertidal zone, which were brought by currents and waves, and disappearance due to low food availability |
[11] | Archidoris montereyensis | Vancouver Island, Canada | May 1969, Oct 1970 | Exposed by low tides | Fluctuations due to fortuitous larval settlement in the intertidal zone. Post-spawning disappearance related to mortality by food scarcity, physical stress by environmental factors (e.g. temperature and dissection) or dislodgment by storms |
[5] | Triopha maculata | Asilomar State Beach, USA | Oct 1969 to Jul 1973 | No | Emergence of individuals from under rocks, influenced by wave action. Disappearance due to death after spawning |
[37] | Onchidoris bilamellata | Wimereux, France | Jul to Aug 1991 | Not mentioned | No evidence of mass aggregations or tidal migrations |
[38] | 10 species (*) | Delta Area, the Netherlands | Jan 1990 to Dec 1991 | No | In species with more than one generation per year, fluctuations are related to prey availability. In species with annual life cycles, fluctuations are related to other factors such as temperature |
[39] | Archidoris montereyensis | Beach State Park, USA | Jul 1994 to Jun 1999 | Not mentioned | Selective larval settlement in response to prey chemical cues and adult aggregations associated with prey density |
[12] | Dendrodoris limbata | Sant Antoni, Spain | Nov 1992, Sep 1994, Feb 1997 to Jan 1999 | Not mentioned | Disappearance related to death after spawning |
[6] | Onchidoris bilamellata | Millport, Scotland | Jul 2006 | No | Subtidal mass migration and aggregation for copulation and spawning due to magnetic cues or mucus trail-following. No evidence of death after spawning |
[40] | Kalinga ornata | Chennai coast, India | Jul–Dec 2011 | No | Fluctuations due to aggregations to breed. No evidence of death after spawning. Disappearance due to migration for more suitable areas (e.g. food availability) |