Conjecture on multiple limit cycles in a predator-prey model with group defence

Let the predator-prey model described in the paper be given, with its interior equilibrium point and model parameters as defined there. Multiple-limit-cycle conjecture. There exist single-parameter regimes under which the interior equilibrium point can bifurcate to produce at least two limit cycles. This conjecture concerns the possibility of multiple concurrent limit cycles, which the authors observe numerically; its general validity is not established.