  The Hermetia illucens insects or the black soldier fly has been attracting a
growing interest in the food and feed industry. For its high nutritional value
on the one hand, and because it is an adequate species for insects in
controlled environmental agriculture systems, on the other. Therefore, several
models describing this larvae's behaviour have been developed in the
literature. Due to the complex nature of living organisms, systems of
controlled environment agriculture are characterised by their strong
nonlinearities. In this paper, we present a three dimensional nonlinear model
describing the black soldier fly dry biomass weight dynamic changes due to the
temperature's influence. In practice, this biomass weight is not measured in
real time. This becomes problematic for applying feedback control strategies
that assume full information of the states. Thus, this work investigates the
observability of the dry biomass of a Hermetia illucens farming batch. The
instantaneous and global observability of the aforementioned model is proven by
constructing an injective transformation between the state space and a higher
dimensional space where the transformed states are observable.
