Contact Processes on Fragmented Domains

Motivated by recent findings of enhanced species survival when fragmented habitats are reconnected through narrow strips land [S. Pimm, and C. N. Jenkins, Am. Sci. {\bf 107}(3), 162 (2019).], we study the effect a corridor connecting two square regions on time three models exhibiting extinction/survival phase transitions: basic contact process (CP), diffusive process, two-species symbiotic (2SCP). We find that generally increases for $\lambda\ge \lambda_c$, where $\lambda$ is reproduction rate $\lambda_c$ its critical value. The enhancement with $\lambda$, largest in 2SCP.