Table 1.

Temperature treatments were defined based on the in situ temperature when experimental water was collected. This became the mean temperature used for both present treatments, which were split into a constant treatment (control) that was held at that temperature, and a treatment that fluctuated 4° above or below that mean every 24 h. We then set constant and fluctuating temperatures with a mean that was 4° (spring and fall) and 5° (summer) warmer than the mean of our present treatments, in order to simulate warmer, future conditions

Temperature treatment	Spring	Summer	Fall
Present-constant	16°	21°	16°
Present-fluctuating	12°–20°	17°–25°	12°–20°
Future-constant	20°	26°	20°
Future-fluctuating	16°–24°	22°–30°	16°–24°