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This is the exciting schedule of topics whic will be discussed as Erden is at sea, hitting some of these topics head-on.....

 

Click on one of the language tabs in the upper right corner to see each week's new Education Program, based on the schedule of topics, in English, Chinese and Spanish - and, the first expedition in the world to ever have ongoing education, tri-lingually!   Get engaged, sit back enjoy, learn, and spread the word.  You're part of history!  Click here to see our Content Release Schedule.

 

Help Support Eden's adventure, to his causes, and our Ocean Recovery Alliance created education program which will follow along on his GO FUND ME SITE.  


 


 

Westbound Rower Education Week 22: Beaked Whales 


Last week we had the pleasure of having Dr. Jay Barlow as a special guest on our live classroom session with Exploring by the Seat of your Pants. Erden was able to join us this time, starting off with talking about his whereabouts and condition before handing off to Jay, who gave a great overview of beaked whales, his research into these animals, and how Erden’s work is already impacting his research. You can watch the recording of the livestream in the video below. 

 

 

Beaked Whales are the species of animals that Dr. Barlow calls “the largest animal you have never heard of.”  They are not as big as the largest of the whales like the blue whale and humpback whales, but the largest can grow up to 11m in length and up to 11 tonnes. Unfortunately, these species are also extremely shy and do not stay near the surface for long, and this contributes to the low number of visual sightings of these marine mammals.

 

The Family Ziphiidae, or beaked whales, are an early offshoot of the toothed whales, first appearing in the early Miocene roughly 20 million years ago. Within the family Ziphiidae there are 6 genera, making up at least 23 different species of beaked whales with new ones still being discovered to this day. They are known to live in the ocean in all parts of the world, however due to their natural behaviour and little time spent near the surface, they are rarely seen, and little is known about them. Even though they are seldom sighted, the Ziphiidae family is the second largest family of cetaceans in existence today following the Delphinidae, the family of oceanic dolphins.

 

Above: The Family Ziphiidae


Beaked whales are unique for several unique features, like its signature beak. Some have a distinctive long narrow beak; some are shorter and flatter to the whale’s head. For a few species, their beak shows resemblance to dolphins, where their snout is noticeably set off the rest of the head by a bulging forehead. Interestingly, even though they are related to toothed whales, beaked whales have very few teeth, usually processing less than four! It is also extremely rare for females and juveniles to have functional teeth, instead they are vestigial teeth hidden under the gum. These teeth are less for hunting prey, but for aggression and fighting between males for food and mates during breeding season. These teeth are also sometimes referred to as tusks.

  

Above: The skull of a beaked whale

 

Another distinctive feature of all beaked whales are the short grooves they have on the throat, converging anteriorly creating a V-shape. These grooves are used for suction feeding, which is the preferred hunting method of beaked whales. Together using its tongue bone and the V-shaped grooves, the beaked whale can generate sub-ambient pressures inside their oral cavity, bringing its prey straight into its mouth. This specialisation towards suction feeding has led to the loss of most or all of its teeth over millions of years of evolution.

 

From a physical point of view, beaked whales can look like oversized dolphins, and maybe a little stretched too. Beaked whales have a streamlined spindle shaped body for maximising efficiency during their long dives. Their pectoral fins are relatively small and fit perfectly in depressions on the side of the body further reducing resistance in the water. The dorsal fins are small and triangular, located about two-thirds down the back of the whale. Their flippers are unique among the cetaceans because there are no notches on the trailing edge at the left and right fluke meet.

 

The coloration of the beaked whales are varied, ranging from dark grey, to a reddish brown to almost white. The head of the whale is often lighter than the rest of the body. Much of the white on the skin especially in males are scars from fights with each other for territory and females. Using their teeth or tusks that only males have, the scars are created from them raking each other and staying on the whale for the rest of their lives. Some of these scars could be used to differentiate between individual whales, but because they rarely surface, use of satellite tracking tags remains the preferred method of studying these whales.

 

    

Above: Fluke of a Bairds beaked Whale (left) , and fluke of a Killer Whale (right)

 

Based on studies related to stomach contents found in beaked whales, it has been found the squid are their preferred prey. To get to their prey, the whales perform deep dives, which can be as long as an hour while hunting in the darkness. Deep dives are generally dives that are greater than 800m (2,625 ft) in depth and are highly stereotypical with most of these dives followed by an extended period of shallow dives, and slow travel and resting near the surface. One of the suggested reasons for the shallow dives are that the whales need to repay the oxygen debt from the deep foraging dives. 

 

Above: Diving habits of two species of beaked whales (Barlow et al., 2013)

 

Like other whales, beaked whales use echolocation to orientate themselves and search for prey in the dark ocean water. They send out a sequence of high frequency clicking sounds away from them, as these clicks bounce off objects, the echoes are received by the beaked whale. These echoes can be used to judge the distance of the prey, and as the echolocating whale gets closer to its target the returning clicks get faster and faster. Given their sensitivity to acoustic signals, beaked whales are negatively known for mass stranding due to ship sonar, which confuses the animals causing them to get lost and beach themselves. Other anthropogenic threats to these species include ocean plastics, entanglement in abandoned fishing gear, hunting pressure and cascade effects of overfishing.

 


Westbound Rower Week 30: Invasive Species

 

If you have not read on Erden’s blog, or listened to the livestream Erden did recently, there are some major updates to the Westbound Row. For one, Erden is no longer finishing his row Hong Kong.  Instead, he is now rowing southwest, around the southern tip of Borneo then finishing his expedition in the southern tip of the Malaysian Peninsula. This means, however, that he will have to cross south of the Equator at one point, so it is unknown whether it will affect one of his world records attempts to cross the Pacific north of the equator. The finishing point, on the Malaysian Peninsula, does allow the record for first North American to Asia (Continent to Continent) to be achieved.

 

After his short stay in Guam, Erden fixed his broken  communication devices, bolstered his supplies, and also added a curtain to the hatch of his stern cabin where he sleeps and rests. The curtain has multiple uses, such as helping to keep sea-spray and salt from entering the cabin, it’s a little shelter from the rain, and could also help with ventilation and temperature control in the cabin. You can think of the cabin as a little greenhouse, and the greenhouse effect also applies to the cabin as it does the planet. The curtain on the outside blocks most of the heat from entering through the window of the cabin, allowing it to be cooler inside.Last week Erden made some time to join us on a live call with Exploring by the Seat of Your Pants, where he goes into a little more detail about his new route and answer some questions classrooms around the world were eager to ask him. Click on the video below to hear some of Erden’s updates.

 

Above: Erden Eruc, Live from Guam (18 Feb, 2022)

 

One of the highlights from the livestream was the story Erden tells about his feathery friend, the Red-Footed Booby which stayed with him on the rowboat for a couple days over Christmas, and this brings us to this week’s topic. On the different categories of species found in a habitat.

 

In a naturally occurring habitat, the species native to the area are what we call native species. These species of flora and fauna could stay in the in its specific geographic location, and if it these species do not occur anywhere else in the world, we call them endemic species. Australia, for example is home to many endemic species like the kangaroo, koala, emu and the platypus. Some species migrate and move around, growing or shifting its geographic region because of climate or location of its prey. When these species enter a new ecosystem, they are considered non-native species. These natural processes happen very slowly, but with the introduction of humans and our ability to travel around the world we have sped up this process. When a non-native species happen to outcompete the habitat it is in, or causes harm to the local environment and species populations, these non-native species are also considered invasive species.

 

Above: Endemic Species of Australia

 

So not all non-native species are harmful to the local environment. In fact, most of the agricultural crops grown today are non-native, where humans have introduced these crops to other parts of the world and widely grown throughout. Historical examples are the introduction of tomatoes, potatoes and corn to Europe after initial European contact with Americas in the 16th century. Without the introduction of these non-native plants to different places around the globe for cultivation, it is interesting to speculate how different our diets today would be.

 

The natural ecosystem of the island of Guam evolved in relative isolation on the evolutionary time scale. Where dispersal and arrival of non-native seeds and animals would be challenging if using only natural means. Birds could potentially bring in different types of seeds if Guam is within their  migration routes, but seed dispersal via this method is usually limited to the chains of islands nearby Guam and in the Marianas. Like most non-native species in the region, the ones in Guam were mainly introduced by humans, either intentionally (e.g ornamental trees), or unintendedly (e.g stowaway on a boat or plane).

 

The most well documented example is the Brown tree snake, which was believed to be introduced as a stowaway from the US near the end of the Second World War. The Brown Tree Snake then thrived in Guam, in an environment with no native snakes, and nearly decimated the native bird population. Without any natural predators, and when the birds have not evolved to face predators such as the snake, the problem was exacerbated. The USDA (Department of Agriculture) has trained dogs to detect these snakes and to keep them from reaching the island. Nobody is exempted from these searches upon arrival, Erden’s rowboat had to be searched for this invasive species as well! Other species that were introduced accidently to Guam include the Coconut Rhinoceros Beetle, Giant African Land Snail,  Greater Banded Hornet, and the Little Fire Ant. All amphibians found from on the island are all non-native, as there are no native amphibian species much like the snake. All of which have a detrimental effect on the native environment, plants, animals and humans.

 

Above: USDA search Erden’s rowboat for Brown Tree Snakes

 

There are also plenty species introduced intentionally include the African Tulip Tree, an ornamental plant known for its sought after reddish-orange flowers. It’s natural ability to quickly produce seeds, and suckers when the trees are cut makes them extremely invasive for Guam, as the environmental conditions are met for this species of tree to thrive. Throughout the 17th and 19th century, the Spanish introduced the Philippine deer, Black Franolins (a game bird), and Carabao (subspecies of water buffalo) which had some cultural significance. The introduction of these species had similar effects as other invasive species, where over foraging and rapid population growth has led to degradation of Guam’s natural forests.

 

   

Above: Brown Tree Snake

More recently, studies have reported that ocean plastics could a vector in which species can migrate across the oceans but attaching themselves to or living on plastic in the ocean. The aftermath of the 2011 Fukushima tsunami also was an example where scientists found many non-native species which have “migrated” by being attached to the tsunami debris and plastic, then following the currents across the Pacific to the United States. In a study which sampled over 600 different floating items, they found 289 Japanese marine species that travelled across the ocean. Of the 289, 30 of the identified species are known to be invasive. In some cases these nonpelagic species, species evolved to live on a marine substrate (marine animals, coastal rocks, Erden’s Boat etc.), have travelled on plastic and tsunami debris for over 5 years.   The tsunami instance did not start this movement of invasive species, but it highlighted, once again, that plastic can be a vector, and carrier, for species across our waters This enhanced our current understanding of these nonpelagic communities, as they were once assumed to be incapable of surviving in the open ocean environments. This has led to additional interest from the scientific community to investigate the availability of trophic resources for coastal nonpelagic species in the open ocean. These studies have also shown that in the historical biogeographic barriers such as the ocean and continent are quickly becoming obsolete and plastic pollution is an example of this effect, creating a opportunity for coastal species to transit ocean basins and to colonise the open ocean and possibly other environments

 

 

Above: Neopelagic community rafting on ocean plastic

 


 

Westbound Rower Education Week 33: Whale sharks and Erden’s Whereabouts

 

As it has been a theme in the past couple weeks, course corrections are still constantly being made. Last we heard from Erden on Westbound Rower, he was on his way south towards Borneo, and then up to Malaysia. Now, he’s changed course and is  instead rowing North towards Legazpi, Philippines and hopefully up the west coast of Luzon Island toward Manila or Subic Bay (depending on weather and ocean conditions). The goal is to anchor at the marine on the Manila waterfront, and potentially present the rowboat and his expedition to the Philippine people as well as Chinese ambassadors and embassy staff whose workplace is around the marina on the Manila waterfront. Erden is still pursuing a visa for China to achieve his mainland-to-mainland row, which he many desires to accomplish. These public relations value the Westbound Rower reaching the Chinese Mainland would be immeasurable and an opportunity for China to welcome another historic achievement to their shore.

 

Above: Legazpi, Philippines

China has an interesting history with coastal rowing, and entered their team (Kung Fu Cha Cha) for the Talisker Whiskey Atlantic Challenge in 2017. The Team consisted of four female rowers, Cloris Chen Yuli, Amber Li Xiaobing, and Tina Liang Mintian from Guangdong and Sarah Meng Yajie from Henan who became the first ever Chinese team to compete in this cross-Atlantic race. The results were beyond imagined, setting four world records including:

 

1. First team from China to row across the Atlantic Ocean.

2. First team from Asia to row across the Atlantic Ocean.

3. With an average age of 23.5, they became the youngest team ever to row across the Atlantic.

4. Their time of 34 days, 13 hours, 13 minutes shattered the previous record of 40 days, 8 hours, 26 minutes set two years ago. The women are now the fastest team to have ever accomplished the challenge as a four-woman crew.

 

With these records already in the bag, it would be a huge boost for the ocean rowers in China to receive somebody like Erden to its shores on the Westbound Row, but also for his bigger vision to accomplish the second human-powered circumnavigation of the planet and an inspiring story to tell the world.

 

Above: Chinese Coastal Rowing Team (Kung Fu Cha Cha)

 

Heading towards Manila has a second objective. In the case the aforementioned could not be achieved before the start of the monsoon season, Erden may have to store the rowboat in Manila until  the monsoon and typhoon season has passed before finishing the Westbound Row which begins around April and ends around November according to historical observations. In this case, a third relaunch may happen in November and the final destination could again be Hong Kong, China,  Vietnam or the Malay Peninsula, but none of these are confirmed, so we see how it develops over the next couple of weeks.

 

On his way there, Erden will pass through a region which is known for sightings of the largest fish in the ocean, the Whale Shark, or if you want to be use its scientific Rhincodon typus (R. typus). These fish usually range from 8 -14.5 metres in length (26-48ft) with females growing larger than the males. By comparison, Erden’s rowboat is only 7.1 metres (23.4ft long) which is smaller than the average sizes of these giants!

 

Above: Whale Shark

 

Whale sharks are the largest fish in the ocean, but their diet mostly consists of small prey like zooplankton and phytoplankton.  The whale shark is a slow-moving, filter-feeding carpet shark and the largest known extant fish species. The largest confirmed individual had a length of 18.8 m. The whale shark holds many records for size in the animal kingdom, most notably being by far the largest living non-mammalian vertebrate. 

 

At times they would also eat larger fish and even squid, though this has been rarely observed. Being a filter feeder, the whale shark has rows of small, pointed teeth designed to catch prey as the fish swims with its massive mouth open. When water enters its mouth as it swims, the water filter through its gill slits, which act like a sieve catching the plankton while letting the water filters out of from the gills. There are only two other types of filters feeding sharks, basking shark (Cetorhinus Maximus), and Megamouth Shark (Megachasma pelagios).


As of current, whale sharks are classified as “endangered” in the IUCN Red List, and in its 2021 assessment of the species, they found the R.typus populations has continued to decline and found an overall decline of over 63% within the Indo-Pacific Whale Shark population over the past 75 years. Population decline in the Atlantic population is lower, where this sub-population has the “vulnerable” status, even though the population decline over the 75 years was still greater than 30%.  Sadly, most of this decline has been due to shark fishing for the use of their fins in shark fin soup and their oil, which is sold as squalene and in many vitamin supplements purporting (without scientific evidence), of medicinal and anti-cancer qualities. 

 

Above: The three filter feeding sharks

 

A whale shark’s mouth can get up to five feet long when opened, and it is so large that a grown human adult could fit inside, but could whale sharks actually swallow you whole? Thankfully the short answer is no, but if we look into more detail into whale shark’s biological features, we find that the whale sharks could not eat you even if it wanted to. The oesophagus, the muscular tube connecting the mouth to the stomach, is only a few inches across which is far too small for a person to fit through. Another study focusing on feeding behaviour of whale sharks found the sharks were rather picky eaters, often rejecting anything that is foreign to their diet and would spit it back out as soon as it entered the mouth. So the moral here is, whale sharks cannot, and will not, swallow you.  They are amazing creatures to see in the wild too, if you get lucky enough to see one near the surface of the ocean.

 

R.typus can be found in shallow coastal and deep waters of tropical and warm temperature seas all around the world. Although the world only has one ocean, there are two distinctive populations of whale sharks, the Indo-Pacific population and the Atlantic population. Population genetic studies suggest a high connectivity among whale shark populations and individuals in the Indo-pacific population have potential to cross ocean basins. One of the longest recorded trans-pacific migrations involved a female whale shark which travelled over 20,000km from the Tropic Eastern Pacific (off the coast of Panama) to the western Indo-Pacific (near the Mariana Trench). This satellite tracking study support a growing body of evidence form both satellite tracking and genetic studies that suggest whale sharks are capable of long-distance travel, and shows a potential passageway via the North Equatorial Current to reach the Philippine Sea and later into the South China Sea. This migration route has many similarities to the Westbound Row, as the North Equatorial Current was vital in getting Erden across the Pacific!

 

Above: Whale Shark global distribution

 

The Philippines is a hotspot for ecotourism, and a well-known tourist spot for those interested in getting a chance to see these friendly giant sharks and perhaps even a chance to swim alongside them. This was not always the case, because historically the country was home to targeted whale shark fisheries, and it was not until 1998 where a national ban on whale shark hunting and establishing several whale shark sanctuaries. One of these sanctuary locations are Donsol, a municipal region in the Sorsogon province at the southern tip of the island of Luzon and also quite near to Legazpi, which Erden will pass as he enters the bay where the whale sharks congregate, and right under the amazing view of the Mt. Mayon volcano. Donsol is considered a hotspot for whale sharks, because of the suitable climate and food abundance it is a good location for their seasonal aggregations. Whale sharks often display fidelity on an annual or interannual basis, meaning they will likely return to a location, such as Donsol. It is this predictability that make whales sharks suitable for wildlife tourism in the Philippines, where more than 500,000 tourists (pre-2019) try to see whale sharks at various sites throughout the country.

 

Above: Mt Mayon, Philippines

 


 

 

 

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