A) Map of the Lough Feeagh and Furnace, Burrishoole Catchment, western Ireland.

Black circles indicate sites sampled in 2009, white circles indicate sites sampled in 2010. An additional site, Shrarevagh River is not shown on this map but lies 4 km north of Shramore River. B) The three stickleback ecotypes found in the Burrishoole; Furnace anadromous, Furnace resident and Feeagh resident. Red circles on Furnace anadromous indicate positions of 17 geometric landmarks; red lines on Furnace resident indicate linear body, BD—body depth, and anti-predator trait, DS1 – 1^st dorsal spine length; DS2 – 2^nd dorsal spine length, PS, pelvic spine measurements.