Influence of environmental variability on distribution and relative abundance of baleen whales (suborder Mysticeti) in the Gulf of California

Abstract

The Gulf of California (GC) is one of the most productive seas in the Pacific Ocean because of several oceanographic phenomena that support many marine mammal species, particularly of the cetacean order. The environmental variability of the GC was analysed during the cold and warm periods of 2005 and 2006 and its effects on the distribution and relative abundance of baleen whales using sea surface temperature (SST) and chlorophyll a (Chl a) concentration. Satellite image analysis allowed us to detect important differences in both Chl a concentration and SST including cold to warm periods, even between the two cold periods and between the two warm periods. The cold periods had the highest number of whales: 99 individuals in 2005 and 183 in 2006, which were distributed along the entire gulf. Fewer animals were recorded in the warm period: 46 individuals in 2005 and 30 in 2006, which were mainly distributed in the northern part of the gulf. We concluded that SST influenced the relative abundance of baleen whales while Chl a concentration influenced their distribution.

Influence of Conditioned Media of Halomonas sp. DH-e on Phycosphere Bacterial Community Dynamics of <i>Prorocentrum donghaiense</i>

“…What's more, Rhodobacteraceae and Alteromonadaceae had a strong oppositional correlation because Rhodobacteraceae was positively correlated with pH, Chl a and DAC, while Alteromonadaceae was negatively correlated with them. The result was also consistent with the report that Rhodobacteraceae could benefit from phytoplankton bloom and its relative abundance had a positive correlation with Chl a [40].…”

“…Interestingly, the abundance of Alteromonadaceae increased and Rhodobacteraceae decreased during the lysis of algal cells. It has been reported that Rhodobacteraceae could benefit from phytoplankton bloom and its relative abundance had positive correlation with Chl a concentration [40]. Our results drew a similar conclusion, which showed that the density of algae cells and Chl a concentration reduces gradually during the algicidal process due to algae cell lysis (Table 1), and Rhodobacteraceae was positively correlated with Chl a and DAC (Fig.…”

“…A large amount of DOC was released during algae cell lysis [41]. Alteromonadaceae could rapidly respond to the disturbance and profited from allochthonous carbon input [40], explaining the increased abundance in the anaphase of algicidal process (Fig. 3).…”

Sea Surface Temperature (SST) Variability of the Eastern Coastal Zone of the Gulf of California

“…Nevárez-Martínez et al [54] obtained similar results when analyzing the distribution and abundance of the Pacific sardine (Sardinops sagax) in the Gulf of California, and its relationship with the environment, determining that the distribution is influenced by the SST and winds that causes upwelling effects. On the other hand, García-Morales et al [55] determined the influence of environmental variability in the distribution of whales in the Gulf of California, based on the SST and Chl a, they obtained that the largest number of whales were during the cold season of the Gulf of California and the lowest number during the warm season, concluding that the SST influence the relative abundance of the whales while the concentration of Chl a influences its distribution.…”

Decreases in encounter rate of endangered Northeast Pacific humpback whales in Southern Costa Rica: Possible changes in migration pattern due to warming events

“…To assess the influence of climatic indices and environmental variables on the encounter rate of humpback whales Spearman correlations were performed (Robinson et al, 2009;Garcıá-Morales et al, 2017).…”