Have any numbers of cats and dogs estimated to be feral on each island? Agreed that the problem of dogs and cats is terrible ecologically, and needs to be managed ecologically with the best informed citizenry. We are not there yet! 

Looking for comparative stats, I found Delaware (twice the size of Big island alone) has a budget of ~$3.1 million and about 200,000 dogs in the state. They have ~15 animal control officers that collect strays and and collected ~4,400 dogs last year. That State has ZERO services to deal with cats.
http://dhss.delaware.gov/dph/oaw/files/dacrec.pdf

The report for Delaware says they need $4-7 per person to adequately manage their Dog services (not including cats or other feral animals, which Hawaii has many more of, I assume)