[R-sig-eco] solving differential equations for ecological models

Greetings - I'm having trouble figuring out an efficient means towards solving for the equilbria in a four-equation model with two herbivores (H1 and H2), and two predators (P and S). Below, I have set the rate of change for these populations to 0 (i.e., equilibrium), then solved. The resultant

Re: [R-sig-eco] solving differential equations for ecological models

Using Mathematica I get the following: H1 <- (apred1*ashark2*eshark2*(ashark3*b2+ashark2*xpred)+ ashark3*eshark3*(-(alpha22*b2*(ashark3*b1+ashark1*xpred))+ alpha12*b1*(ashark3*b2+ashark2*xpred))-alpha22*apred1*ashark3*b2*xshark+ apred2^2*ashark1*epred2*xshark-apred2*(-(ashark3* (ashark1*b2*epred2*