Below, please find a report on a new MAMMAL BIG DAY FOR NORTH AMERICA on August 4, 2004 by Sarah Allen, below and Peter Pyle, below on right and Floyd Hayes, below on left. Part of their day included the Shearwater Journeys' pelagic trip to the Farallon Islands.
On 4 August, Peter Pyle (the mastermind), Sarah Allen and I made an all-out attempt to break the previous mammal “big day” record for North America of 17 native species, set independently by Peter Pyle and Richard Stallcup. We began at Point Reyes at midnight and managed to break the record before dawn, recording our 18th species at 5:25 am! By the time we reached the dock in Sausalito at 7:15 am we had already tallied 21 species. We added 7 new seven species of marine mammals during a Debbie Shearwater pelagic trip to the Farallon Islands, where we saw the lingering NORTHERN GANNET (obviously our best bird of the day). After returning from the boat trip we spent another 6 hours searching for mammals but added only 2 more species, finishing our big day at 10:20 pm with 30 native mammals (29 detected by all; 3 heard only), 3 introduced mammals and 5 domesticated mammals. We used a bat detector, which converts ultrasound signals of bats to audible