February 2011

24 February. We took off from Chatham on a cold morning and made our way up the backside of the Cape, just three miles offshore. Within a couple of minutes, we had our first right whale sighting of the flight, which upon closer observation, turned out to be three right whales subsurface feeding. While one individual was feeding alone, the other two individuals were subsurface feeding in echelon. A bit further north, additional right whales were sighted. We observed one of right whale subsurface feeding, and the other traveling. We continued our flight over the Bay, but we did not see another right whale until we were a bit further south. There, we observed a couple whales that were taking long dives, possibly indicating that they were feeding on zooplankton beneath the surface.

February 24. The cruise began in excellent sighting conditions with calm seas, unlimited visibility, and moderate temperatures and ended in fair to poor conditions with an increasing southwest wind. Eight of nine regular Cape Cod Bay stations were sampled with an oblique and a surface tow net. In total, eight to nine right whales were sighted, along with harbor seals, white sided dolphins, and one harbor porpoise.

The right whales were scattered along the southern and western margin of the bay with the activity being primarily long dives. During the cruise, a moderately rich surface and mid water zooplankton resource was collected at each station. Pseudocalanus spp dominated the samples, with a mix of Calanus finmarchicus and late stage Centropages spp. The resource in the upper mid water and surface of the bay nowhere exceeded the estimated threshold for feeding by right whales.

17 February. After a week or so of windy weather, we were anxious to get back up in the air and see what was going on in Cape Cod Bay. We took off from Chatham airport and headed to the southernmost part of the bay. The first right whale sighting of the day was a juvenile, traveling alone. Once we had the photographs we needed to identify the individual, we continued onward. As we traveled north along our track lines, we soon realized it was going to be a moderately busy day. We ended the day with approximately thirteen right whales, which included two whales skim feeding in echelon. After a full day of work, we headed south along the backside of Cape Cod toward Chatham, and were treated to an excellent view of the moon rising over the ocean.

17 February. The vessel based right whale research cruise was undertaken in coordination with the PCCS aerial survey team. Sighting conditions throughout the day were excellent with small swells to calm seas, moderate temperatures, and unlimited visibility. During the cruise four regular and three special stations were sampled using nets and hydroacoustic equipment in order to assess the available plankton biomass in the water column (in collaboration with J. Warren, Stony Brook University). In total, seven to nine right whales were sighted, as well as one fin whale. The majority of the sightings were in the eastern quadrants of the bay, with behaviors including social activity and long diving.

The zooplankton resource in the eastern portion of the bay appears to be entering a transition period with an initial assessment indicating a mixed resource including several of the taxa of calanoids known to release feeding behavior: Pseudocalanus spp., Centropages spp., Calanus finmarchicus, and possibly Temora longicornis. Collections during the cruise suggest that the transition to a Pseudocalanus/Calanus dominated resource has begun and that subsequent cruises will likely observe increased favorable conditions for feeding by right whales. In view of these observations, the continued presence of right whales is likely, however a substantial increase either in numbers of whales or in the frequency of near-surface feeding behavior in the near term is not yet anticipated.

11 February. We took off from Chatham airport and headed up the backside of the Cape and conducted the survey in a north to south direction. The weather started out rather windy on the east side of the Cape. As we continued on into the Bay we hoped the wind would die down and the sea state would improve. The weather in the western portion of the bay was slightly better than in the east. As we continued along our survey the wind increased to the point where we decided it was inhibiting our survey and we headed back to Chatham airport. We did not observe any marine mammals during this survey.

7 February. With the promise of good weather for the day, we took off from Chatham airport to survey Cape Cod Bay in a south to north direction. It was not long before we spotted a pair of whales that were slowly traveling at the surface, making it much easier for us to get the photographs necessary to identify them. Often times, during the winter months the whales are going on much longer dives and not spending very much time at the surface, making it very difficult for us to get good photographs of them. We recorded a total of seven right whales for the day.

7 February. The sea state and sighting conditions were excellent, on Monday, February 7th, with unlimited visibility and moderate temperatures during the cruise. The regular zooplankton stations were sampled to describe the influential zooplankton resource, marine mammal distribution, and environmental settings.

During the cruise, four to five right whales were sighted in the northeast quadrant and the eastern margin of the southwest quadrant of the bay. All were observed either on moderate to long dives or undetermined subsurface behavior. The surface and midwater zooplankton resource has continued to decline from levels that were previously observed and was dominated by a mix of Centropages spp. and Pseudocalanus spp. The resource in the upper midwater and surface of the bay did not exceed the estimated threshold for feeding by right whales.