Thursday, June 20, 2019

A Sei whale and lots of common dolphins with babies in São Miguel


We managed to start this day with some common dolphins! These resident species had some calves and juveniles frolicking in the waves. 







Then we tried to find the sperm whales that our look-outs spotted, quite far off the west-coast. As the sperm whales dove, we then tried to find them using the hydrophone, but no luck unfortunately. The waves in this area got rougher, the sperm whales can dive for at least 45 minutes, and we were running out of time. But wait! Our lookout managed to spot another surprise for us. So, we continued, and indeed, our look-out led us to a sei whale! The baleen whales are still around! This sei whale seemed to be traveling, so we could follow it underwater. We could see it quite clearly underneath the surface. So in the end, it was worth the wait!


In the afternoon the wind was stronger then in the morning and this made it a bit more tricky for the lookouts and the boats to search for animals. After some time our patience got rewarded and we found the common dolphins. 
As there were many boats we left this group after a short while and came a cross an other one, which were interested in approaching our vessels. We saw them very well. Adults, juveniles and many calves and some of them were leaping and breaching. One seemed to be quite excited as its usually white belly turned rose. So this group of dolphins made our trip worthy and people enjoyed them.






Wednesday, June 19, 2019

Today full of suprises with a Sei whale and at least 5 beaked whales

Today it was a great day with a quite calm ocean and little wind. 
From our various boats we managed to encounter a total of 6 different species. 

In the morning we had Risso’s dolphins, bottlenose dolphincommon dolphins and a sei whale










In the afternoon we went to the north coast where the common dolphins, Risso's dolphins, Sowerby’s beaked whales and sperm whales were observed. We had the chance to see several sperm whales fluking and like this we can identify an individual. 
Beaked whales
Beaked whale

Beaked whales





Risso's dolphins

Risso's dolphins
Today one of them was Pm 447 which was baptised today as Ronalda by some clients who donated us a picture. She was found today for the third time, as always, on the north coast; once in October 2017, then in September 2018 and now today. What a successful day!








Sperm whale

Sperm whale diving


Sperm whale





Tuesday, June 18, 2019

5 species in 1 day in São Miguel

After 3 days on land due to bad weather conditions, we finally went to the sea and it couldn't have been better. Throughout the day, we sighted 5 different species! 

We started the morning with few different activities: whale watching, swimming with dolphins and a full-day experience including a trip to the famous Vila Franca do Campo Islet.

From our different boats, we encountered different groups of dolphins: 

- Common dolphins feeding and socializing really close to us, 





- Striped dolphins with their characteristic way of swimming,


- And bottlenose dolphins with calves jumping and swimming around our boat.



The highlights of the day? 
Our most loyal sperm whale in the morning, who delighted us with its impressive fluke: Mr. Liable!



In the afternoon, the surprise was a beautiful and majestic Sei whale.



It feels so good to be able to go out again, hopefully the sun shines a bit more tomorrow!

Saturday, June 15, 2019

Why do some animals eat plastic?

In the past 60 years, the use of plastics and other synthetic materials has rapidly expanded worldwide. The new uses and applications developed for these materials have made them more available to anyone of us, making harder to live without them our daily lives.



A bottlenose dolphin with plastic in its dorsal fin

For marine life, avoiding plastic has become a main issue: plastic and other debris have noticeably increased their presence in the ocean, particularly in the last decades. Many of these plastic products degrade very slowly. Some are buoyant and remain suspended at the sea surface for a long time, and some sink and remain on the bottom for years or even decades. 

Therefore, plastic suppose an increasingly significant threat to marine fauna, including mammals, seabirds, turtles, fish and crustaceans.



Another bottlenose dolphin with plastic in its dorsal fin

Marine animals can get entangled on the debris, which can limit the animal ability to hunt or to avoid predators, or cause deep wounds on the skin or even drowning. Cases of animals that consume plastic waste are more common every day. 

The ingestion of those plastic materials may block the digestion process, damage the stomach and release toxic chemicals. All these mechanical effects affect many marine species in all ocean areas and justify recognition of persistent plastic debris as a major form of ocean pollution. 



The obvious question arising is, why do marine animals eat plastic?

Scientists believe that animals consume plastic debris because some of the shapes and sizes of this debris share similarities with their prey.

One of the earlier known occurrences of plastic ingestion was in 1962 for an adult Leach's storm-petrel collected off Newfoundland (Rothstein, 1973). To date, plastic trash is found in 90 percent of seabirds and virtually everyone will be consuming it by 2050 (Wilcox et al., 2015). Robert H. Day (1980) maintains that seabirds, at least in Alaska, eat plastic because they mistake it for natural prey items. For example, in all the parakeet auklets Day examined, most (94%) of the ingested plastic consisted of small, light brown pieces that bore a striking morphological resemblance to the small crustaceans on which the birds typically feed (Coleman & Wehle, 1984).



Our biologists removing litter from the sea

The plastic of the ocean also has an appetizing smell for some sea creatures. A study published in 2016 revealed that some seaweed grows easily on the plastic of the ocean, and the decomposition of this material releases an odor called dimethyl sulphide (DMS) that attracts hungry animals (Savoca et al., 2016).

While seabirds choose from a wide array of plastic objects during foraging (including raw particles, fragments of processed products, bottle caps), marine turtles consistently select only one item -plastic bags. They seem to mistake plastic objects for potential food items. 

For turtles, transparent polyethylene bags apparently evoke the same feeding response as do jellyfish, the major food item of leatherback turtles, and subsidiary prey for greens, hawksbills, loggerheads and Ridleys turtles. 

Plastic bags have been found in the digestive tracts of at leasty four of the seven species of marine turtles.  Recent studies indicate that leatherback turtles and green turtles are at the greatest risk of both lethal and sublethal effects from ingested marine debris (Schuyler et al., 2013).

Another study, published last year (Macali et al., 2018) released the first evidence of plastic in the body of a jellyfish. It’s unclear why jellyfish are attracted to plastic. After some time floating in the ocean waters, plastic begins to wear, and thin microbial films tend to coat the surface. Scientists believe that these microbial films or some molecules present in the plastic decomposition process may attract jellyfish.

Regarding marine mammals, in the last few months, several news from all over the world highlighted stranded whales and dolphins with their stomachs full of plastic. Sometimes this plastic is visible, but the presence of “microplastics” has become even normal on stranded marine mammals. 

Recent studies found microplastics in 94% of the common dolphins stranded in Galicia (Hernández-González et al., 2018), and in every stranded cetacean analysed in the UK coast (Nelms et al., 2019).


Marine mammals such as seals, pilot whales, pygmy sperm whales or beaked whales are all affected, eating mostly plastic sheeting or bags. Sometimes with impressive quantities, such as the 17 kg found in a sperm whale washed up in the coast of Spain; or the sperm whale found in Indonesia with more than 80 plastic bags in its stomach.


Consequences of eating plastic

It could be that plastic ingestion is inconsequential to the health of the animals. 
This, however, does not appear to be the case for many marine organisms that eat plastic. As the problem gains notoriety, it is certain to be revealed as being even more widespread than is now recognized. One indication of this is the occurrence of secondary ingestion, in which plastic consumed by animals feeding at low trophic levels is passed on through them to higher-level consumers (Coleman & Wehle, 1984).
A more obvious effect of plastic pollution is the aesthetic one. Whether we venture deep into the woods, high atop a mountain, or out on the ocean to escape the trappings of civilization, our experience of the natural world is often marred by the discovery of human litter. Even more disturbing is the sight of a bird entangled in fishing lines or a whale rising to the surface with its flukes tangled in nets. Unfortunately, such observations are becoming more and more common, another consequence of plastics at sea.

Written by Andreia Vieira 

References:
Coleman, F. C., & Wehle, D. H. S. (1984). Plastic Pollution: A worldwide oceanic problem. Parks9(1), 9-12.
Day, R. H. (1980). The occurrence and characteristics of plastic pollution in Alaska's marine birds (Doctoral dissertation).
Hernandez-Gonzalez, A., Saavedra, C., Gago, J., Covelo, P., Santos, M. B., & Pierce, G. J. (2018). Microplastics in the stomach contents of common dolphin (Delphinus delphis) stranded on the Galician coasts (NW Spain, 2005–2010). Marine pollution bulletin137, 526-532.
Macali, A., Semenov, A., Venuti, V., Crupi, V., D’Amico, F., Rossi, B., ... & Bergami, E. (2018). Episodic records of jellyfish ingestion of plastic items reveal a novel pathway for trophic transference of marine litter. Scientific reports8(1), 6105.
Nelms, S. E., Barnett, J., Brownlow, A., Davison, N. J., Deaville, R., Galloway, T. S., ... & Godley, B. J. (2019). Microplastics in marine mammals stranded around the British coast: ubiquitous but transitory?. Scientific reports9(1), 1075.
Rothstein, S.I. (1973). Plastic particle pollution of the surface of the Atlantic Ocean: evidence from a seabird. Condor 75:344-366.
Savoca, M. S., Wohlfeil, M. E., Ebeler, S. E., & Nevitt, G. A. (2016). Marine plastic debris emits a keystone infochemical for olfactory foraging seabirds. Science advances2(11), e1600395.
Schuyler, Q., Hardesty, B. D., Wilcox, C., & Townsend, K. (2014). Global analysis of anthropogenic debris ingestion by sea turtles. Conservation biology28(1), 129-139.
Wilcox, C., Van Sebille, E., & Hardesty, B. D. (2015). Threat of plastic pollution to seabirds is global, pervasive, and increasing. Proceedings of the National Academy of Sciences112(38), 11899-11904.




Friday, June 14, 2019

Sperm whales everywhere!

 Today in the morning, we went again really far from Ponta Delgada, the animals are wild and we don't choose where they are so we went to see them.



 


Remains of a squid, the favourite snack of sperm whales

It was a big male sperm whale that was in a area of female sperm whales, we saw also the females. Then on get way back we spotted a group of bottlenose dolphin and they make us go to lunch with a smile in our face.




Foto: Iñaki Cabo


In the afternoon, we went to another area closer than the sperm whale area from the morning. We found a group of striped dolphins with their tipycal behaviour, jumping and tavelling all time. 



Then we could see another male sperm whale, this was alone, as we know male sperm whales are solitary and they share moments with females when they go for reproduction. 


This sperm whale was doing shallow dive constantly, but we were lucky and a group of bottlenose dolphin brought us to the sperm whale, and with all dolphins around the sperm whale decided to go for a feeding dive showing the tail. 



Common tern with prey



Full of animals here out of Sāo Miguel yeaaah. Do you want to join us


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