2024 Annual Gray Whale Report for Laguna San Ignacio & Bahia Magdalena

2024 Annual Gray Whale Report for Laguna San Ignacio & Bahia Magdalena

By Steven Swartz

May 20, 2024

a waterfall coming down from a whale fluke

2024 Gray Whale Research Program Summary

 

Declining gray whale body condition, low calf counts, and higher mortality rates were documented in Laguna San Ignacio and in the Bahía Magdalena (BM) complex beginning in the winter of 2018 and were indications of the pending gray whale Unusual Mortality Event (UME) which continued from 2019 through 2023. Observations throughout the gray whale’s range during the 2024 winter indicated an overall improvement in the whales’ body condition, and fewer gray whale strandings. On this evidence, NOAA closed the gray whale UME in 2024 (NOAA Gray Whale UME Working Group 2024).

In the winter breeding and calving lagoons of Baja California Sur, however, counts of female-calf pairs were the lowest recorded since our abundance surveys in these winter aggregation and breeding areas began in 2006, suggesting a major decline in the reproductive capacity of this population in recent years during the UME. In Laguna San Ignacio the highest number of single adult (non-calf) whales counted in vessel surveys during 2024 was 201 whales on 25 February, which was higher than the counts observed at this time during the previous five winters of the UME. In contrast, counts of females with calves remained low in all areas. The 2024 calf counts were the lowest recorded in Laguna San Ignacio numbering fewer than nine calves throughout the birthing period from January through February, with the highest count of only 15 female-calf pairs observed on 14 March. The highest gray whale survey count in Bahía Magdalena was obtained on 24 February in the most southerly aggregation area of Bahía Almejas and was 243 single adult whales but no female-calf pairs. In central Bahía Magdalena gray whale counts were greatest on 23 February with 35 adult whales and no female-calf pairs. In the northern Canal de Santo Domingo, a high count of 17 single whales was observed on 19 February, and a count of only two female-calf pairs.

In this report we present our initial findings during the 2024 winter concerning the status of gray whales, their condition and reproduction, and our outreach. Open complete report with the link below.

Read Entire Report here