June 16th and 17th, masses of mostly smaller-sized snapper species, one pound or less, deeper water specimens, and a few larger fish, were found floundering on the surface, barely alive and eventually dying and drifting onto the beaches from north of Punta Gorda to Palmilla.
In early March while doing some research about the sudden disappearance of Humboldt squid, I was introduced to William Gilly, a professor of Biology at Stanford University's Hopkins Marine Station. Gilly was a member of the team of writers and scientists who re-created Steinbeck's voyage in 2004 to once-remote waters chronicled in author John Steinbeck's classic book, 'Log From the Sea of Cortez' and recently he has been part of a group that has been studying the effects of El Nino Sea of Cortez Humboldt squid population.
In June, 2010, they only found small 8-inch mature squid spawning in the Guaymas Basin…totally abnormal. The preceding summer, big squid were in the midriff islands and off northern Sonora this winter.
"Now they are nowhere to be found," Gilly said, "we traveled throughout the Guaymas Basin, up midriff islands area, and found very few squid. Commercial boats have also been searching without success."
Gilly observed that, "From February through March this year the mixed surface layer has gotten steadily shallower -- along with an extreme fall-off in oxygen. Yellowfin tuna and billfish probably would have a really hard time at oxygen concentrations below half of the peak values plotted here -- so right now they would be compressed into the top 60 feet or so. If the bait is missing it would be stressful, but if it is bountiful, it would be good for the species."
In 2009 and 2010 a similar trend developed during the spring, but it was much less severe. This is definitely unusual -- these are features normally associated with tropical eastern Pacific waters farther to the south.
Recently, unusual cold winds along with cooler currents from the south caused water temps to plummet into the 60s along the Sea of Cortez coast from Baja's tip to Las Frailes which resulted in off-color murky green water extending twenty miles from shore.
June 16th and 17th, masses of mostly smaller-sized snapper species, one pound or less, deeper water specimens, and a few larger fish, were found floundering on the surface, barely alive and eventually dying and drifting onto the beaches from north of Punta Gorda to Palmilla.
Locals, who could not remember anything similar happening in the past, were quick to volunteer a variety of possible causes: By-catch from commercial netting, red tide, natural occurrence, nuclear fallout from Japan, drastic current/temperature change, air bladder rupture, limited oxygen levels or maybe a terrorist poison attack.
Gilly who had sounded the alarm back in March commented that with the combination of winds, cold water and lots of chlorophyll, it sounds like upwelling, either from the wind or possibly it has something to do with the several early hurricanes far to the south.
Gilly went on to say: "Hurricanes often churn up a lot of nutrient-rich cold water to the surface quickly, much like normal wind-driven upwelling and the effects are often left in its wake. I suspect that severe south winds resulted in the strong local event and a red-tide bloom. Some harmful algal toxins may have bloomed. Knowing the actual oxygen levels at the time of die-off would shed some light on the event."
"Coincidentally, we witnessed something similar, June 12th to the 14th, in the Bahia Las Animas and San Rafael areas south of Bay of LA on a research cruise."
"The entire Salsipuedes Canal was a deep red-brown color, surface temperature was 18C rather than 27C nearby, and oxygen was very high. The air on deck was colder than inside the air-conditioned ship. Chlorophyll readings reached 70 mg/cm -- a garden-variety productive bloom would be more like 10-20 mg/cm and everyday blue water is typically <1."
"We did not see any die-offs in this area, but we had great difficulty trying to keep squid alive in our temperature-controlled, holding tanks on deck. Here the squid all died in less than 8 hours because they were held in recirculated surface water, so they could not escape the bloom by going to depth. In all other areas we worked, from Guaymas to Santa Rosalia to San Pedro Martir, the squid routinely lived 2 to 3 days in the same conditions."
The explanations for the event are all across the board. From the old standby 'El Nino' to my personal favorite 'Terrorist attack'. It seems the consensus by the experts is that lower oxygen levels along with some algal toxin associated with a huge bloom were at the root of the event.
