Cetacean mortality in the Patagonia Argentina has increased significantly in recent years and the causes behind this alarming increase are varied. A report by the Whale Conservation Institute (ICB) reported that in 2012 there were 116 whale deaths, of which 113 were calves, a figure that doubles the 61 deaths in 2011.
The scientists of the UCI They have proposed three possible causes for this increase in mortality: accidental strandings, the seagull attack that feed on their dorsal fat, and exposure to solar radiationDespite these hypotheses, experts say they are still unable to fully explain why this phenomenon has escalated so rapidly.
Mortality caused by red tide
One of the main hypotheses that has been corroborated in recent years is the incidence of the so-called red tide or “harmful algal blooms,” which have been responsible for many of the whale deaths in the region. In fact, as of October 2022, at least 30 deaths of southern right whales due to the presence of paralyzing toxins produced by these algae.
Algal blooms are a natural phenomenon that can be exacerbated by the environmental imbalance generated by the global warming and the dumping of inadequately treated industrial or agricultural waste. These discharges often feed algae that, once massively proliferated, produce toxins that affect both whales and other marine species.
Impact of seagulls on whales
Another factor contributing to the mortality of these marine giants is the attack of the kelp gulls, a species that has learned to feed on the blubber that whales have on their backs. Although this behavior is not new, it has worsened over time. Wounds caused by repeated pecking by seagulls can become infected, thus weakening the health of whales, especially calves that, being smaller, do not have the same ability to defend themselves or heal quickly.
In response to this, the authorities of the province of Chubut have implemented a plan to reduce the population of seagulls in the most affected areas. This plan has been criticised by environmentalists, but is considered a necessary measure to preserve the population of southern right whales, an already vulnerable species.
Whales as sentinels of marine health
One of the most important conclusions that has been drawn from recent studies on whale deaths is that these animals act as sentinels of ocean healthThe high frequency of deaths in short periods of time has alerted scientists about problems in the marine ecosystem. Factors such as increased pollution, excessive maritime traffic and climate change are causing changes that affect not only whales, but the entire marine ecosystem on which they depend.
In fact, it has been proven that the toxic algae The toxic substances that kill whales also have devastating effects on other species, including birds and sea lions. In some cases, the accumulation of toxins in plankton can trigger mass mortality events, affecting entire chains of marine biodiversity.
Tourism and conservation in Peninsula Valdés
The Valdés Peninsula, located in the province of Chubut, is considered one of the most important sanctuaries for the southern right whale. Every year, between April and December, around a third of the world's population of these whales arrive at the protected bays of the peninsula to reproduce or give birth. This has turned the place into a tourist attraction, attracting more than 100.000 people who want to observe these imposing mammals up close, which can reach up to 16 metres in length and weigh 50 tonnes.
While tourism brings economic benefits to the region, it also poses significant conservation challenges. The large influx of tourist boats can create Stress on whales, affecting their natural behaviour. Authorities have implemented strict regulations to limit the number of vessels and ensure that sighting practices do not disturb the tranquillity of cetaceans. However, the risk of collisions between ships and whales, as well as the impact of underwater noise, remains a relevant concern.
Another factor that aggravates this situation is the growing number of Plastic and marine litter in the waters surrounding the peninsula. Whales, like other marine species, can accidentally ingest this waste, causing blockages in their digestive system and, in some cases, agonizing death.
In short, whale mortality in Patagonia is not a simple phenomenon to address. Various factors such as red tide, gull attacks, plastic pollution, and climate change are wreaking havoc on the southern right whale population. While significant efforts have been made to mitigate these effects, it is essential that both governments and the international community step up their actions to protect not only whales, but also marine ecosystems as a whole.