In this installment of our Ask a Scientist Q&A series Dr. Greg Stone, CI's Chief Ocean Scientist, answered questions about marine mammals and the state of the ocean from the CI community. Due to the tremendous response – over 75 questions from around the world – some questions were omitted or consolidated. Thank you for your support and understanding.
Click on each question to expand or close the answer. Expand all
GENERAL QUESTIONS ABOUT MARINE MAMMALS
How do marine mammals demonstrate their memory? What experiences or information do they tend to recall?
- Tracy from the United States
Hi Tracy, thank you for your question! This is a very interesting topic, and research has taken place with both seals and dolphins on problem-solving and short-term memory. Some examples of demonstrated memory and the experiences these animals can recall would be how they forage for food, predator avoidance, and how they are able to distinguish individuals through vocalization.
If massive marine life declines, will this affect the oceans' ability to absorb carbon dioxide, thus adding to global warming?
- Joseph from the United States
Hi Joseph, thank you for your question! The role of the oceans in the global carbon cycle is without doubt very significant; they represent the largest long-term carbon sink, and they store and redistribute CO2. Of all biological (or "green") carbon that is captured worldwide, over 30 percent is captured by marine organisms and, thus. is termed "blue" carbon. Over 90 percent of the earth's CO2 is stored and cycled through the oceans.
Large organisms such as whales are responsible for exporting carbon to the deep sea from the surface of the water – especially the ocean's vegetated habitats like mangroves, seagrasses and saltmarshes. Such habitats cover less than 0.5 percent of the seabed, yet these "blue" carbon sinks are responsible for 50-70 percent of all carbon stored in the ocean sediments. Loss of blue carbon sinks creates a real threat.
Here at CI, our marine climate change scientists are studying the importance of mitigating the effects of climate change as well as finding key adaptation strategies to reduce the impacts of climate change on the world's oceans.
I've been reading a lot about the Phoenix Islands Marine Protected Area, but it seems mostly focused on fishes and corals. Has anyone done any kind of research on marine mammals in this region?
- Jake from the United States
Hi Jake, thanks for your question! During September 2009, I led a team of 15 people from such organizations as the New England Aquarium, National Geographic, the US Fish and Wildlife Service and Conservation International on an expedition to the Phoenix Islands. The aim was to conduct a study of the reefs and to document the marine life there, which included the presence of marine mammals. Here is a link to our dispatches from the field, which were sent via satellite phone:
Expedition: Phoenix Islands Protected AreaCan ocean mammals such as whales, dolphins, etc., live – at least temporarily – in fresh water (lakes, rivers)? Which ones do and do not? Thanks
- Fernando from Costa Rica
Hi Fernando, thank you for your question! Marine mammals are able to live in freshwater, at least temporarily, although over time they would become exhausted due to the lack of buoyancy provided by freshwater and a lack of food availability. Marine mammals can also have issues with their eyes and skin after prolonged exposure to freshwater. There are freshwater marine mammals, such as river dolphins, that can be found in rivers and estuaries.
What effect will krill depletion in the southern oceans have on whales and other marine mammals?
- David from the United States
Hi David, thank you for your question! As you know, climate change is a big issue these days and is having serious impacts on the marine environment. As water temperatures are rising, the ecosystem is being affected in a number of ways. In reference to krill, these shrimp-like organisms depend on sea ice to survive. In areas of the Southern Ocean around Antarctica, there is a pattern forming between the rise in water temperature and lower survival rates of South Atlantic right whale calves; it is believed this is due to a drop in the availability of krill. This has also been seen in fur seals and blue whales.
What is the biggest threat to marine life at the moment, and what can be done to stop it?
- Michelle from Australia
Hi Michelle, thank you for your question! Ocean ecosystems must respond simultaneously to multiple threats – unsustainable fishing, global climate change, habitat destruction, invasive species and pollution – that together magnify the effects of individual threats.
Overall, there are two major barriers to re-establishing a prosperous ocean. Firstly, a lack of global consensus on the status of ocean health makes it difficult to rally the global public and decision-makers around collective actions to improve it. Secondly, fragmented ocean governance restricts comprehensive ocean management, weakens enforcement of regulations and favors short-term interests over long-term ecosystem needs and human well-being.
Here at CI, we have an ambitious plan to restore and maintain a prosperous ocean through a number of global solutions which we hope will spur a revolution in marine governance and management. The result will transform ocean health and benefit the people who depend on marine resources for their livelihoods and well-being.
First, we need a globally accepted benchmark of ocean health that inspires government, corporate and civil society actions and measures the effectiveness of marine conservation efforts. Second, we need solutions that influence fisheries policy and markets to reverse deteriorating ocean health worldwide. Third, we need to pioneer new models, such as oceanscapes and seascapes, for managing and recovering ocean health at scale.
Here are some links to further information:
In a natural life span, how many miles does the average whale swim? How far can a calf swim before s/he's weaned?
- Cara from the United States
Hi Cara, thank you for your question! It's tough to give an answer to this, as it will differ between species. But the gray whale, which is one of the longest migratory mammals, can travel up to 5,000-7,000 miles in each direction of its migration, so 10,000-14,000 miles/year. If we look at the average life span of the gray whale, it can be between 50-60 years, so they could cover a large number of miles over their entire life span. Here is an interesting article that recently came out on whale migration:
WEBSITE: Humpback whale breaks migration recordAs for how far a calf can swim before it is weaned, consider the gray whale and its population dynamics on the Western seaboard of the U.S. In the latter part of the year, the adults head south towards Baja, and it is here that the calves, once born, will stay for 2-3 months before they travel with the females north again. So during the period that they are weaned, which can be up to 7-8 months, they will travel approximately 5,000-7000 miles.
Is it possible that there are marine animals bigger than the blue whale and unknown to modern science?
- Charles from the United States
Hi Charles, thank you for your question! It's certainly quite common these days for species new to science to be discovered; in fact, Conservation International's RAP program conducts expeditions in some of the most remote places on Earth and regularly finds new marine and terrestrial species. See the following link for more information:
IN DEPTH: Expeditions and discovery As for your question: Although the oceans are 95 percent unexplored, it would seem unlikely that we would see a species new to science that is so big. Typically, the new discoveries are much smaller species such as insects and fish.
How strongly does the disruption of life cycles at the ocean floor affect larger marine life further up the food chain?
- Jonathan from the United States
Hi Jonathan, thank you for your question! This is an interesting topic; one example of how life cycles at the ocean floor can be disrupted is through the process of bottom-trawling, which is a destructive fishing technique where a heavy net and weights are dragged across the seafloor. This has a devastating effect upon communities in the benthic zone, or the lowest level of the ocean, and it can destroy vast areas of the seafloor. In essence, bottom-trawling is like the effects of a bulldozer.
Here is further information on bottom-trawling:
http://www.mcbi.org/what/destructive_fishing.htm As for how this affects marine life further up the food chain, a single example can be seen in seal populations off the coast of New Zealand. As their fish prey disappear, they are being forced to seek other fish species to survive. In many cases, these fish are not as nutritious. Over time, the seals' reproductive and survival rates are impacted.
Dear Dr. Stone, My grade 3 class wants to know: Where did whales come from? Why do they look different? How do they sleep?
- Allen from Canada
Hi Allen, thank you for your question! Whales actually came from the land and evolved to become marine creatures. Their ancestors were in fact fur-covered land mammals that would rarely go near the water. Today, they have adapted into whales which feed upon fish & plankton, have forelimbs which modified to become flippers, and propel themselves through the water using their large tails. All of this was discovered through the study of fossil records.
As for how they sleep: Dolphins don't fall into a deep sleep the same way humans do. This is largely because while humans breathe without thinking about it, dolphins must consciously take a breath each time. So if they slept the way humans do, dolphins would stop breathing!
Instead, it seems dolphins rest from time to time, slowing down and being very relaxed to restore themselves, but do not fall into a deep sleep like humans. Observations of dolphins and whales have determined that they have two basic methods of "sleeping." The first is where they rest quietly in the water column either horizontally or vertically, the second is where they will sleep while close to another animal; this is very similar to how humans take short naps.
What is the current picture of the social life of blue whales in the oceans?
- Harri from Finland
Hi Harri, thank you for your question! Blue whales, as you may know, are the largest species in the world, and they can be found throughout the world's oceans barring a few exceptions. Socially, although they may travel on their own or in groups, it is most common for them to travel in pairs.
Can you recommend any books or other publications dealing with marine mammals within the East African region?
- Martin from Kenya
Hi Martin, thank you for your question! Two good books that come to mind would be:
- Marine Mammals of the World: A Comprehensive Guide to Their Identification
- Encyclopedia of Marine Mammals
I live near a river delta area. Scientific reports show that Irrawaddy dolphins are found in the area; however, I never meet anyone who has seen them. How do I spot Irrawaddy dolphins? Do I have to use a kayak/canoe rather than motorboat?
- Asti from Indonesia
Hi Asti, thank you for your question! Typically, Irrawaddy dolphins occur in both fresh and estuarine waters and prefer coastal areas near the mouth of rivers; they can be seen in the freshwater plume that occurs when a river meets the ocean. Inland, in mangrove/river habitats, they can occur where river channels converge or diverge, or downstream from sharp, meandering portions of the river. It seems as though you could probably see them from the riverbank.
For more information on their distribution, check out the following link:
http://www.iucnredlist.org/apps/redlist/details/15419/0/rangemap Dear Dr. Greg Stone, I would like to know: Among the whale species nowadays, which one is the most antique?
- Daniel from Peru
Hi Daniel, thank you for your question! I assume here you mean most unique, or unusual? I would have to say that manatees are very interesting and unique animals; and they occur in Peru, too (the South American manatee lives there). See the following link, which shows some pictures of these highly interesting and unusual mammals!
http://www.arkive.org/amazonian-manatee/trichechus-inunguis/ Which mammals live in the Indian Ocean? Apart from that, I would like to know about corals. How can we identify corals and sea weeds, and what kind of corals are living in the Indian Ocean?
- Anuradha from Sri Lanka
Hi Anuradha, thank you for your question! A large number of marine mammals can be found in the Indian Ocean; examples would include the spinner dolphin, common bottlenose dolphins, common & Antarctic minke whales, sei whales, blue whales, sperm whales, etc. For your second question, see the following link, which is an interesting article on coral species in the Indian Ocean that are able to withstand the effects of climate change:
WEBSITE: Diversity of Corals, Algae in Warm Indian Ocean Suggests Resilience to Future Global Warming, Science DailyWhat marine mammals are the most critically endangered right now, and what would be the potential impact (if known) if they disappear?
- Laura from the United States
Hi Laura, thank you for your question! One of the most threatened marine mammal species right now is the "vaquita," also known as the Gulf of California harbor porpoise. It is currently listed as Critically Endangered on the IUCN Red List, which is a way of assessing the conservation status of a species.
Here is a little more information:
http://www.iucnredlist.org/apps/redlist/details/17028/0 As species such as this become extinct, they are lost forever, and their absence can have untold impacts on the ecosystem and its biodiversity – which, in turn, can impact humans.
How long can dolphins and whales swim underwater without taking air from the surface again? I teach English at schools, and some children wondered about that, but I couldn't give them an answer.
- Patricia from Argentina
Hi Patricia, thank you for your question! On average and depending on the species, dolphins can stay underwater for 5-10 minutes without taking air from the surface.
Where can I get a chart with all of the basic information on cetaceans? I'd like to help in teaching people about sea life, and I need basic info.
- Marcos from Costa Rica
Hi Marcos, thank you for your question! A useful website to visit is that of the American Cetacean Society, which has some interesting online information as well as materials you can purchase. Here are some useful links:
What kind of barnacles grow on whales? And do the barnacles hurt the whales?
- Eddie from the United States
Hi Eddie, thank you for your question! Barnacle species found on whales are typically specific to that species of whale. For instance, the barnacle Coronula diadema, is found only on the skin of humpback whales and nowhere else. Barnacles typically do not hurt the whale, and the relationship is very much a symbiotic one where they both benefit.
Hi, I was wondering about sea mammals and how endangered they are. Are there real numbers? Thanks for your time.
- Carlos from Peru
Hi Carlos, thank you for your question. The best way to find the status of sea mammals is to check the IUCN Red List. This site shows the conservation status of plant and animal species and will in some cases list estimates of their numbers. Here are some examples:
Hello Dr. Stone, Is it true that some marine mammals have or carry Omega-3 and that they are hunted because of it, besides being hunted for their meat/flesh? Isn't it possible to get Omega-3 in an artificial way?
- Manuel from Paraguay
Hi Manuel, thank you for your question! The origin of these oils is the synthesis of long-chain omega-3 polyunsaturated fatty acids by algae and phytoplankton. Fatty fish such as herring, mackerel, tuna and salmon are a source of omega-3 fatty acids due to the fact that they consume these algae and phytoplankton; in addition, some plants and nut oils also contain them. For more information on omega- 3 fatty acids, check out the following link:
http://www.umm.edu/altmed/articles/omega-3-000316.htm My seven-year-old has three questions. How many teeth does a great white shark have? Is it true that we know more about space than our own oceans? Could you tell me more about the Pacific barreleye?
- Sara from Canada
Hi Sara, thanks for the questions! Great white sharks can typically have around 3,000 teeth arranged in a number of rows. As for the oceans and how much we know, to put things in perspective, 95% of oceans are largely unexplored, so there are lots we haven't seen!
And finally, in reference to the Pacific barreleye: These deepwater fish are found in the northern Pacific between Japan and the Bering Sea in Canada, and as far south as Baja, California. They are certainly very unique-looking, possessing a transparent head and long, tubular eyes. Here is a link that includes pictures of this species of fish:
WEBSITE: Macropinna Microstoma Mystery Solved - The Transparent Head And Tubular Eyes Of The Barreleye Fish How close are scientists to understanding the sonar language of whales and dolphins, and when could these scientists expect to be able to actively communicate with them?
- Marcia from the United States
Hi Marcia, thank you for your question! Quite a lot of research has gone into this. One organization in particular, the
Pinniped Cognition & Sensory Systems Laboratory based in California, studies marine mammals focusing on their sensory, cognitive and behavioral ecology.
This type of research ties in to the effects of noise pollution on marine mammals and how such pollution affects their ability to communicate.
I live in Brasilia, capital of Brazil. What are the statistics and numbers reflecting the real situation of marine life today? A big hug and congratulations on your beautiful and important work and its contribution to the planet.
- Luciana from Brazil
Hi Luciana, thank you for your question and kind words! Here are some current statistics that paint quite a bleak picture of marine life today;
- 52 percent of the world's fisheries are fully exploited, 20 percent are over-exploited and 17 percent are significantly depleted or recovering
- 90 percent of large predatory fish are gone
- Each year, commercial fishers catch and discard 7 million metric tons of bycatch, including hundreds of thousands of marine mammals, sea turtles and seabirds
- Pollution-caused "dead zones" cover 245,000 square kilometers (more than 95,000 square miles) worldwide, a total area larger than the United Kingdom
- 20 percent of the world's coral reefs have been lost, and another 20 percent are degraded
A bleak picture; but here at CI, we are working hard to turn the tide and to work to restore and maintain a prosperous ocean!
How does a walrus eat with those huge tusks? Don't they block the food?
- Ben from the United States
Hi Ben, thank you for your question! Walruses typically feed on mollusks such as clams and in one day can eat up to 6 percent of their body weight! They find food by scouring the ocean floor, searching through the mud; they use their long whiskers to detect their food, as visibility is limited. They move their snout through the sediment as they search for food, although they do not typically use their tusks for digging.
I have read in an article about sea otter numbers declining fast due to the sudden predation of whales (because the whales' other prey has declined due to us). Is that still a very big problem, or has the situation improved?
- Simona from Denmark
Hi Simona, thank you for your question! Yes, you are right; there have been instances in some areas where whales are now preying on sea otters. In the late 1990s it was discovered that Alaska sea otter numbers were rapidly declining, and it was later found that this was due to the fact that they were becoming the prey of killer whales. These animals are so large and require such huge volumes of food; it gives you an indication of why the otters have been hit so hard.
Since marine mammals, for the most part, travel all over, how can any country make a determination about how they are to be treated or affected, as no country can actually own them?
- Valerie from the United States
Hi Valerie, thank you for your question! Our work here at CI looks at marine solutions to help turn the tide on the plight of the oceans; this includes scaled-up management of large areas of the ocean called seascapes and oceanscapes. Both are new approaches to building government, corporate and civil society coalitions aimed at improving ocean governance. Since they cover very large areas of ocean, the benefits of this approach are substantial and can influence the survival of threatened species. Here are some links to CI's work with further information:
Any answers to why marine mammals beach themselves?
- Anca from the United States
Hi Anca, thank you for your question! In some cases, single animals may beach; in other scenarios, mass beachings can take place. There is quite a bit of variability between species, and location can also play a role, but there are a number of factors that, it is thought, can cause the beaching of marine mammals such as dolphin and whale species. These include: the animal is sick, navigation issues, panic/stress, difficulties in seeing the beach slope, adverse weather, the chasing of prey, etc.
What sources do you highly recommend to edify my two home schooled children regarding requisite global management?
- Gregory from the United States
Hi Gregory, thank you for your question! If you are referring to marine management globally, then one form of this is Marine Protected Areas (MPAs). By definition, a protected area is described by the IUCN as "A clearly defined geographical space, recognized, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values." This applies to all terrestrial, freshwater, coastal and marine areas. For MPAs, since 1999, the following definition has been used: "Any area of intertidal or sub-tidal terrain, together with its overlying water and associated flora, fauna, historical and cultural features, which has been reserved by law or other effective means to protect part or all of the enclosed environment" (Kelleher 1999). Here is a good link for further MPA information:
http://www.mpa.gov/aboutmpas/definition/In addition, here are links to some of the marine management that CI is leading using a scaled-up approach, whereby very large areas of the marine environment are governed through a coalition of partners:
Why isn't there more being done to protect the seals? From climate change to hunting, there isn't much being done ?
- Kelly from the United States
Hi Kelly, thank you for your question! There are a number of organizations that focus on specific species and their conservation; here at CI we offer global solutions which, while not specifically focused on marine mammals, will provide many benefits to them.
Our program looks at: creating a global health index for the oceans, creating more sustainable fishing (which is also linked to the types of fishing gear that are used and ensuring that impacts on the marine environment are minimal), and managing large areas of ocean at scale. All of these provide benefits to threatened species.
I heard while watching the move "The Cove" that dolphins are self-aware. Is this true for whales? How is it measured?
- Robert from the United States
Hi Robert, thank you for your question! This is certainly an interesting topic of study. For many years, this type of research has taken place with bottlenose dolphins whereby a small mark was made on the dolphin's bodies and they were then observed viewing their reflection in a mirror. They were clearly aware that they were looking at themselves and that something about their bodies was a little different. Scientists are now saying that they have observed self-awareness in whales, too; this came from field observations.
Hello, I read a rumor some time ago that whales know when they are about to die, and hours before their death, they dive deep down to abysses and die, forming a cemetery, much like elephants do. I wanted to make sure it's true – or not. Thank You.
- Paola from Mexico
Hi Paola, thank you for your question! I am not familiar with any research involving this behavior in whales. When whales die in the oceans, they become food for a large number of other species – typically beginning with the larger fish species, then the smaller worms and invertebrates, and then finally the bacteria that feed upon the bones and any fat that remains, which can take many decades.
When Nudibranchs acquire new tools for survival via the consumption of other Nudibranchs, is there a period of digestion that is toxic and life-threatening to the predator?
- Si from the United Kingdom
Hi Si, thank you for your question! Nudibranchs are certainly interesting marine organisms, with over 3000 known species, including some that eat other nudibranchs and others that are toxic. I am not aware of any period during their digestion when they are at risk of their prey, including other nudibranchs, and it is not known how they remain immune to the poisons. In many instances, the poisonous creatures they consume are used by the nudibranchs, who re-purpose the poisons for their own use; even non-poisonous nudibranchs are able to safely consume poisonous species.
Is anything being done to address the problem of collisions between whales and ships? I understand that the only reason shipping lanes are in known whale migration areas is financial. What is being considered to discourage this?
- Kevin from the United States
Hi Kevin, thank you for your question! This is not something that CI is specifically looking at, although there are organizations that have programs for this. The National Oceanic and Atmospheric Association (NOAA), through its fisheries work, has a program that focuses on ship strike reduction in North Atlantic right whales.
It looks at understanding the whales' distribution patterns and encourages responsible behavior for boating (speed restrictions through specific areas, vessel routes, etc.) Here is a link to a recent success story that involved changing the shipping lanes going into Boston to help reduce the risk of ship collisions with whales:
WEBSITE: Changes in Vessel Operations May Reduce Risk of Endangered Whale Shipstrikes1. Are there certain cetaceans that have healthy readings of contaminants & if so, where are they located? 2. Have ocean temperatures affected migration & increased mortality? 3. Can we use satellites to arrest unlawful cetacean capturers?
- Andrew from Canada
Hi Andrew, thank you for your questions! Regarding contaminant levels: This has been typically difficult to measure due to the lack of widespread and long term studies. In 2002, a study focused on the concentrations of organochlorines in marine mammals, drawing upon data from a number of sources. It was found that marine mammal species from the northern hemisphere's temperate fringes, especially fish-eating mammals found in Europe and North-America's mid-latitudes, had the highest concentrations of contaminants. Those from the southern hemisphere and in the tropical and equatorial fringes of the northern hemisphere had much lower levels.
There is definitely a link between water temperatures and biodiversity. As waters warm, marine species will begin to re-distribute themselves. In some marine mammals, there are concerns that warmer waters will begin to affect the availability of food sources such as krill, which is one of the main food sources for a number of whale species.
Satellite transmitters are being used for tracking a number of marine mammal species to determine their migration routes. As for using satellites to prevent unlawful cetacean capture, I am unsure if, and at what level, this technology is being used. Here at CI, working with our partners, we have been using GPS transmitters to track fishing vessels around the Galapagos Islands to monitor their movements and to ensure they do not enter a marine protected area and fish illegally. Here is a link to more on this:
FEATURE: A Longer LifePALEONTOLOGICAL QUESTIONS
In this millennium, have there been (and where, at what date) new discoveries of late-surviving archaeocetes?
- Rhys from Australia
Hi Rhys, thank you for your questions! To answer this one specifically, there are 2 somewhat recent discoveries that come to mind of archaeocetes – a group of animals that lived tens of millions of years ago and that are commonly known as "ancient whales." There is 1998's
Himalayacetus subathuensis, which was found in oyster-rich limestone in the Simla Hills of the Lesser Himalaya Range, Himachal Pradesh, India; here is a link to the paper that came out in 1998:
WEBSITE: A new Eocene archaeocete (Mammalia, Cetacea) from India and the time of origin of whales The second discovery was published in 2001, and was a new genus of Dorudontine. The discovery,
Chrysocetus healyorum, was found in a quarry in South Carolina's Orangeburg country. For more information, click on the following link:
PUBLICATIONS: New Genus of Dorudontine Archaeocete (Cetacea) from the Middle-To-Late Eocene of South Carolina (PDF - 1.77 MB)
EDUCATION RELATED QUESTIONS
Danica from the United States, Ally from the United States, Michelle from Australia and Trisha from the United States presented questions related to educational and career opportunities.
Hi Danica, Ally, Michelle & Trisha, thank you for all of your questions! There is certainly not one single route to take when it comes to your education and professional career, and we have marine staff from a variety of backgrounds who work here at Conservation International.
Certainly if you are interested in the marine realm, then a degree in marine biology is a great way to start; if you feel like further education, then you could specialize by doing a master's degree. This would allow you to focus your interests on such topics as marine mammals, ocean conservation, marine policy, etc. From there, if you intend to get into research and want to lead such projects, then a Ph.D. is a good way to go – although it involves significant time and dedication.
I hope this helps. Good luck in your respective endeavors!
TOURISM RELATED QUESTIONS
Katie from the United Kingdom, A. Fry from the United States, Debby from the United States and Michelle from Australia presented questions regarding tourism and marine mammals.
Hi Katie, a.fry, Debby & Michelle, thank you for your questions! Ecotourism works only when it yields economic benefits to local people, supports conservation and reduces the human impact of travel. It requires the active and educated participation of tourists and the travel industry alike, and it involves everyone from the visitor to the tour operator and airline to the hotelier to the local labor force to agriculturists to individual conservationists.
Conservation International brings these parties to the table in key locations to develop nature-based tourism strategies that are community-driven and conservation-focused. For more information, see the following link:
IN DEPTH: EcotourismRegarding marine mammals and tourism (whale watching, etc.), I think it is good as long as it is done responsibly. There are guidelines in many countries, including the U.S., that ensure that whales and dolphins are not bothered or hurt in the process of being watched. As long as the marine mammals are safe, it is good to raise awareness among the public with such activities. You can see bottlenose dolphins off the U.S. East Coast year-round. Whales are not all that common off Daytona Beach.
'THE COVE' DOLPHIN HARVEST AND WHALING RELATED QUESTIONS
Mike from the United States, John from the United States, Connie from the United States, Maryanne from the United States, Gordon from the United States, Jordan from Canada and Victor from Thailand had questions about whaling and dolphin harvest with some references to the movie "The Cove".
Thank you for your questions that reference whaling and the documentary, "The Cove."
Historically, whaling was far more devastating than it is today; in the past, whale populations were overharvested and declined to very low levels. As for "The Cove," this movie certainly received substantial media coverage and helped to bring to light marine mammal conservation as a worldwide issue. I think the film will lead to broader discussions on species conservation.
QUESTIONS ABOUT SLEEPING HABITS OF MARINE MAMMALS
Blue from the United States, Robert from the United States and Craig from the United States provided excellent questions about the sleeping habits of marine mammals.
Hi, Blue, Robert, & Craig, thank you for your questions!
Not a lot is known about sleeping in dolphins except that they do not sleep in the same way humans do. This is largely because we have involuntary breathing (i.e., we breathe without thinking about it) and dolphins have voluntary breathing (i.e., they have to consciously take a breath each time). Therefore dolphins can never sleep in the way we sleep, or they would stop breathing. Instead, it seems, they rest from time to time, slowing down and becoming very relaxed to restore themselves. But they do not fall into a deep sleep like humans.
Observations have determined that this "sleep" has 2 basic forms. In the first, dolphins rest quietly in the water column either horizontally or vertically. In the second, they will sleep while close to another animal; this is very similar to how humans take short naps.
It is thought that while sleeping, whales and dolphins will shut down one side of their brain in unison with their opposite eye, which monitors for predators and also signals when a fresh breath is needed. After a period of around two hours, the marine mammals reverse the process and shut down the other half of their brain. This process is termed cat-napping.
DUGONG AND MANATEE QUESTIONS
Joshi from India and Suzy from the United Kingdom asked questions about conservation efforts form manatees and dugongs.
Hi Joshi and Suzy, thank you for your questions! The dugong is a very interesting mammal. As you mention, they are often called sea cows due to the fact that they graze on submerged aquatic vegetation. They are typically found in coastal and inland waters:
WEBSITE: Dugongs' global distributionI am not aware of any specific projects or funding, but the following link (the UNEP Dugong Status Report and Action Plans for Countries and Territories) lists some of the current projects that are taking place to protect this species. The report is broken down by geography and covers both existing and suggested conservation measures:
DOWNLOAD: Dugong: Status Report and Action Plans for Countries and TerritoriesAs for manatees, there are 3 known species, all of which are listed as Vulnerable on the IUCN Red List – so are all under a level of threat. Here are some links to these manatee species:
For each of these species, the page also lists conservation actions.
In the US., the U.S. Fish and Wildlife Service is the federal agency that protects the nation's most threatened species. It is responsible for protecting the West Indian manatee, known as the Florida manatee. In the U.S., this species is listed as Endangered; see the following link for further information:
WEBSITE: US Fish & Wildlife Service: West Indian manatee (Trichechus manatus)OIL SPILL RELATED QUESTIONS
Jen from the United States, Colleen from the United States, Shelley from the United States, Alma from Mexico, Suzanne from the United States, Susan from the United States and A. Robbins from the United States inquired about the Gulf oil spill and the impacts this will have on ocean health and biodiversity.
Thank you for your questions that reference oil spills. The recent oil spill in the Gulf of Mexico has certainly brought this issue to the forefront of marine work around the world.
Unfortunately, Conservation International does not actually do any work in the Gulf and primarily focuses on other parts of the world. I would suggest that for further specific information, you visit the following online sources:
WASTE AND PLASTICS RELATED QUESTIONS
Can't you get the "Prototype This" team at the Discovery Channel to invent a plastic-eating robot, that derives power from consuming plastic, to clean up our beaches and possibly our oceans of plastic debris?
- Robert from the United States
Hi Robert, thank you for your question! It would be a fun project to work on; I like the idea. although we would need to build a lot of machines! One of the best things to do is to limit our use of single-use plastics, and to reuse and recycle as efficiently as possible.
What, if any, is the impact of plastics in the oceans on the health of cetaceans, etc.?
- Dave from the United States
Hi Dave, thank you for your question! Cetaceans, like most marine life, can sometimes mistake plastic pollution for food. Whales, dolphins and other sea life experience a decline in health, and in some cases, death is a result of ingestion. Most plastics don't biodegrade and, unless removed, will remain in the sea for hundreds of years, breaking up into ever-smaller particles.
Once the plastics break down into smaller particles, marine life mistakes the particles for food. The plastic, along with its chemical compounds, enters the food chain. Big fish eat smaller fish, and people eat all kinds of fish. So not only does it have a negative impact on cetaceans and other marine life, it also has a negative impact on human health as well.
What can factories do to throw away their waste in a way that the ocean is not polluted?
- Lorena from Bolivia
Hi Lorena, thank you for your question! Factories can be more responsible on how they dispose of their waste. Untreated waste and wastewater should never be released into waterways – the waste, chemicals, debris, etc. will eventually make their way to the oceans, and it also pollutes freshwater along the way! The biggest challenge is promoting and enforcing those practices on a global level. Not all countries maintain the same best-practices for waste disposal and in some places the regulations are not enforced. The best thing to do from a consumer standpoint is to be responsible for the products you buy. Try to buy from companies who take responsibility for their manufacturing process and supply chain by using chemicals that are not devastating to the environment. Consumers have more power than they realize.
Are there any plans to clean up the plastic accumulation in the Pacific Ocean?
- Doris from the United States
Hi Doris, thank you for your question! The Pacific Plastic (or Garbage) Patch is an incredibly challenging situation. The sheer size of the patch is incredible, about twice the size of Texas. In addition to its size, the debris is mostly made up of plastic that has already started to break down, causing a soup-like mix.
As plastic degrades, it breaks down into tiny particles that make it extremely difficult to skim with a net. There are many people interested in cleaning the patch up; however, I have not heard of a viable solution yet. Undertaking this type of cleanup would be a huge investment in time and money and require partnerships at a large scale. The best thing an individual can do right now is to be more responsible with their plastic usage and make sure we are not continually adding to the problem.
STATUS OF THE WORLD'S OCEANS
Nelson from East Timor and William from the United States asked about the current global state of our oceans and marine biodiversity.
Hi Nelson and William, thank you for your questions! People need a healthy ocean to prosper. Our ocean is the Earth's primary life support system, comprising 99 percent of our world's biosphere. It is essential to human survival and well-being, but its future is in doubt. Here are some current statistics that paint quite a bleak picture of marine life today;
- 52 percent of the world's fisheries are fully exploited, 20 percent are over-exploited and 17 pecent are significantly depleted or recovering
- 90 percent of large predatory fish are gone
- Each year, commercial fishers catch and discard 7 million metric tons of bycatch, including hundreds of thousands of marine mammals, sea turtles and seabirds
- Pollution-caused "dead zones" cover 245,000 square kilometers (more than 95,000 square miles) worldwide, a total area larger than the United Kingdom
- 20 percent of the world's coral reefs have been lost, and another 20 percent are degraded
Here at CI, we are working hard to restore and maintain a prosperous ocean by offering solutions on a global scale.
LEARN MORE: Check out our marine website to learn more about our strategy to turn the tide.– Dr. Greg Stone
Chief Ocean Scientist
Conservation International