The blue-tipped puffer is a migratory bird that is found along the coast of this state in summer months. The puffers enjoy the seeds of Thomson's Mulberry trees; because these trees are plentiful in the state's Coastal Park, traditionally many blue-tipped puffers would be found in the park during summer months. Ten years ago, the grey fox, a primary predator of the puffer, was re-introduced into the park, and its numbers have been thriving. Over that time, we have seen many fewer puffers in the park during the summer months. Clearly, the puffers are choosing to spend their summers elsewhere. Which of the following would be the most important to determine in order to evaluate the argument?
【选项】Whether other coastal areas in the state have seen an increase in the number of blue-tipped puffers over the last decade.