The best beaches are Praia do Farol (in town) and Praia do Paraíso and the more remote Baía do Sol in the north. Stingrays may be present – let them know you're entering the water by shuffling your feet and they'll most likely move off.
There's nowhere worth recommending to stay on Ilha do Mosqueiro – everyone visits on a day trip from Belém.
Food can be a bit hard to find, especially late at night and on weekdays. The restaurants at Hotel Farol and Hotel Fazenda Paraíso serve good, standard dishes for R$12 to R$25. There are lots of barracas (food stalls) in the main square and on Praia do Farol.
The island’s main town, Vila Mosqueiro, is on the southwest tip of the island. Av Beira Mar, the main drag, starts in town at Praia Farol and runs northward along the shore past Praia Chapéu Virado, Praia do Murubira, Praia Marahú and Praia do Paraíso. The other main road is Av 16 de Novembro, which intersects with Av Beira Mar between Praia Farol and Praia Chapéu Virado at a small plaza and church.