Bahamas' Dolphins: Post-Hurricane Dorian Update
The Bahamas Marine Mammal Research Organisation (BMMRO) is using Loggerhead Instruments' recorders to document changes in dolphin detections and ambient noise as Abaco recovers from Hurricane Dorian, which devastated the Bahamas in September 2019. Scientists at BMMRO recover and redeploy recorders approximately every two months, as Covid restrictions allow.
An initial analysis of the first six months of post-hurricane data has been completed by a Masters' student from the University of St. Andrews and shows an expected increase in dolphin detections as the ambient noise has decreased. These changes are due to a 90 percent reduction of boats in the area, a lingering effect of the hurricane.
Bahamas’ researchers use a variety of Loggerhead acoustic recording devices. Something old, something new, something donated, something blue.
First Recordings of African Manatee Vocalizations in the Wild
Loggerhead Instruments' LS1 has been successfully deployed in Lake Ossa, Cameroon to record vocalizations from the African manatee, also known as the West African manatee. The African Marine Mammal Conservation Organization (AMMCO) collaborated with an international team (Eric Angel Ramos from City University of New York, Athena Rycyk from New College of Florida and Mumi Kikuchi from Wildlife Research Center of Kyoto University) to collect over 800 African manatee vocalizations.
The African manatee (Trichechus senegalensis) can be found along the western coast of Africa, ranging from Senegal to Angola. AMMCO and their partners hope to use the vocalization data to assess the impact of the proliferation of giant salvinia (Salvinia molesta), an invasive, floating aquatic fern which may be negatively impacting the manatees. The team also hopes to use the new equipment to acoustically monitor for other aquatic megafauna such as cetaceans.
Visit their website for more information.
Battle of the Batteries
We put three battery brands to the test to see which would last the longest in Loggerhead's passive acoustic recorders.
The Test
One pack of 3 D-cells for each brand
Record 60s
Sleep 60s
96 kHz sample rate
Amazon Basics was the winner, running for 26 days, whereas Energizer lasted only 20 days. Sorry Energizer bunny.
In summary, using Amazon Basics alkaline batteries with a 50% duty cycle:
Snap would run 26 days
LS1 would run 104 days
LS1X would run 208 days