ELECTRONIC SUPPLEMENTARY MATERIAL Reproductive state affects reliance on public information in sticklebacks Webster MM & Laland KN Subjects and husbandry 1 1 1 1 0 Ninespine sticklebacks were collected from Melton Brook, Leicestershire, UK (GRID REF: SP 00) in October 00 and again in October 00 and taken to our laboratory where they held in groups of 1 in L aquaria for four to five months before being used. Each aquarium contained a layer of coarse sand, an internal filter, and artificial vegetation for cover. The light: dark regime was held at 1: hours and the temperature was initially maintained at C. They were fed daily with frozen bloodworms. They were held under these conditions until the following February. In February the groups of 1 fish were moved into 0L aquaria. Additional vegetation was provided and the temperature was raised to 1 +/- 1 C in order to bring the fish into reproductive condition. All experiments took place between February and April 00 and February to April 0. In each year we only used fish collected the previous October and all fish were experimentally naïve, and unfamiliar with the experimental apparatus. 1 EXPERIMENT 1. PUBLIC-INFORMATION USE IN REPRODUCTIVE AND NON-REPRODUCTIVE NINESPINE STICKLEBACKS 1
Apparatus 1 1 1 1 0 1 We established an experimental tank (0 by 0 by 0 cm, water depth 1 cm) containing a 1 cm deep layer of coarse sand (Figure S1a). Yellow plastic bars, 1 cm wide and 1 cm deep, secured to the base of the tank and rising to the surface of the sand divided the tank into three zones (i in Figure S1a). Each outer zone contained a goal area (the shaded triangle ii), demarcated by the yellow plastic bars. Two colourless Perspex demonstrator chambers ( by 1 by 1 cm, water depth cm) were placed inside each end of the main tank (iii). These held the demonstrator shoals. In the corner of each demonstrator tank was a feeder used to deliver prey (iv). The feeder consisted of a by cm base, 0 cm tall tower. The front wall, facing the demonstrators was transparent so that they could see the prey as it was delivered. The rear wall was white to maximise the visibility of the prey. The side walls were opaque blue, so that the observer in the centre of the tank could not see the prey. Demonstrators were unable to reach the prey until it sank to the bottom of the feeder, but were able to attack it as it fell. The front wall of the feeder stopped 1 cm short of the floor of the tank, allowing the demonstrators to eat the prey once it had reached the bottom of the feeder. Prey deliveries consisted of two mm long pieces of thawed frozen bloodworm. These were small enough to be consumed with minimal handling by the demonstrators, ensuring that the observing focal fish could see the feeding behaviour of the demonstrators, but not the prey itself. Screening on the outside of the test tank prevented the fish from seeing the experimenter as the prey were added. Housing the demonstrator in watertight chambers ensured that no chemical cues originating from the prey were available to focal fish, since these may provide direct information about feeder location and prey density. This ensured
1 1 1 1 that focal fish could only base their patch choices upon visual cues received during the demonstration phase. The centre of the tank held the focal fish during the demonstration phase. This section was divided from the two end thirds of the tank by removable Perspex walls set in runners on the side of the tank (v). A cm wide section of each of the removable Perspex walls in contact with this side wall was left transparent, giving a clear view from the holding unit into the demonstration chambers. The remaining section of the removable walls was covered with opaque white plastic film in order to prevent the demonstrators in one demonstration chamber from observing those in the other. The focal fish was housed within a by cm base, 1 cm tall holding unit constructed from clear Perspex (vi). This was attached via a monofilament line to a cm long arm at the top of the tank, allowing it to be raised. The holding unit was placed against one the side walls of the main tank, in the centre of the central third, so that it faced the feeders in the two demonstrator chambers. A cm diameter, cm tall artificial plant was added to provide cover for the focal fish during the test phase. This was placed directly opposite the holding unit, against the facing side wall of the main tank (vii). The configuration of the experimental tank during the test phase is shown inset in Figure S1a. The exterior of the tank was screened in black plastic and the focal fish was observed via a high definition camera (Canon HG0) fixed 0 cm above the tank and connected to a monitor (Powervision 1. inch waterproof LCD-TV). 0 1 Figures of test tanks FIGURE LEGEND Figure S1. (a) Plan view of the public information experimental arena used in experiment 1(not to scale), established within a 0 by 0 by 0 cm tank, water depth 1 cm, containing a 1 cm
1 1 deep layer of coarse sand. (i) Yellow plastic bars, 1 cm wide and 1 cm deep, secured to the base of the tank and rising to the surface of the sand. (ii) The preference or goal area used to determine preference for either feeder. (iii) Perspex chambers holding the demonstrator shoals. (iv) The feeder used to deliver prey. (v) Removable Perspex walls set in runners on the side of the tank. (vi) Holding unit housing the focal fish prior to the beginning of the choice phase of the trial. (vii) A cm diameter, cm tall artificial plant was added to provide cover for the focal fish during the test phase. Inset figure shows the configuration of the test tank during the choice phase of the trial. (b) Plan view of the asocial foraging experimental arena used in experiment (not to scale). Each grid square represents a cm wide and cm deep square pit, filled to 1 cm deep with coarse sand. The grey square in the top left represents the starting position of the fish and held a removable holding unit (dashed square). The star indicates the location of a prey patch. Please refer to the main text for a full explanation of the experimental arenas and procedures. 1 1 0 1
Figure S1. a) i vii ii iii v iv vi b)