Cooperation is thought to be a necessary condition to solve collective dilemmas such as climate change or the sustainable use of common pool resources. Yet, it is poorly understood how situations pervaded by thresholds shape the behaviour of humans facing collective dilemmas. Here we provide empirical evidence that resource users when facing thresholds maintain in average cooperative behaviours maximising their individual earnings while taking care of future group opportunities to thrive. A dynamic game with 256 Colombian fishermen helped us investigate behavioural responses to the existence of thresholds (probability = 1), risk (threshold with known probability of 0.5) and uncertainty (threshold with unknown probability). The game was framed as a fishery ground with the likelihood of a climate event that abruptly reduced the recovery rate of the fish stocks on which the fishermen earnings depended. Uncertain thresholds made fishermen maintain higher levels of cooperation than when the risk of thresholds is known, but risk had a stronger effect at reducing individual fishing effort. If cooperation increases in the face of thresholds, then communicating uncertainty is more policy relevant than estimating precisely where tipping points lay in social-ecological systems.