  An enviromental-random effect over a deterministic population mo\-del, a
resource ({\it e.g.}, a fish stock) is introduced. It is assumed that the
harvest activity is concentrated at a non predetermined sequence of instants,
at which the abundance reaches a certain predetermined level, for then to fall
abruptly a constant capture quota (pulse harvesting). So that, the abundance is
modeled by a stochastic impulsive type differential equation, incorporating an
standard Brownian motion in the per capita rate of growth. With this random
effect, the pulse times are images of a random variable, more precisely, they
are "stopping-times" of the stochastic process. The proof of the finite
expectation of the next access time, {\it i.e.}, the feasibility of the
regulation, is the main result.
