****************************************************** ANIMAL BEHAVIOR AND SURVIVAL ****************************************************** ********************************************** BEHAVIOR ********************************************** *********************** EFFECTS OF DARKNESS *********************** __________ QUESTION: Since during the winter in Antarctica you rarely see the sun, how does this affect animal behavior and emotions? ANSWER from Dr. Michael Castellini on February 6, 1995 There is no information on animal emotions relative to lack of sunlight in the Antarctic. Emotions are a very hard thing to test and this issue has not been addressed. However, the behavior does change with the darkness, at least in seals. They dive differently in the day than in the night. At night, their dives tend to be much more shallow. We believe that there is a clear reason for this: their food (squid and small fish) come closer to the surface at night to eat the creatures that they feed on. So, while there is a day/night difference, it is not from the point of view of the impact of the dark on the animal directly, as much as it impacts their ability to hunt and find food. Since all of the animals in the Antarctic are pretty much marine animals, they have to deal with the dark all the time when they dive deeply. *********************** REACTION TO HUMANS *********************** __________ QUESTION: Have you met any animals that were not happy to see you? ANSWER from Terry Trimingham, Field Operation Communications Center, McMurdo Station, Antarctica, on February 3, 1995 The animals I tend to see here most often are Adelie Penguins, Weddell Seals, or South Polar Skuas, and none of them are used to seeing humans. For the most part, I am not able to get close enough to an animal to tell what they are thinking because they are usually quite a distance from me. Weddell seals usually just lie there and rarely act excited or ANYTHING. They have no land predators and don't seem to care about you. Penguins and skuas will go out of their way to see what you are doing; they are curious types. When I was at Palmer Station years ago I encountered many skuas that did not seem happy to see me at all. They are very fierce about defending their young. If they think you are too close to their baby, they will zoom down out of the sky with both feet extended, and actually try to knock you down! They can almost be successful, too. I didn't pay attention the first couple of times and got a few good whaps on the side of the head (it HURT!). Here at McMurdo we are not that close to any nesting areas, so the birds we see are just curious, not furious. Palmer also sees different kinds of seals, among which is the fur seal. Fur seals have large teeth, can move VERY quickly, and know how to defend themselves on land. I never met one up close, because I chose to keep my distance! ************** HIBERNATION ************** __________ QUESTION: Are there animals in Antarctica that hibernate, and if so, what are they and where do they hibernate? ANSWER from Laura Powers on February 10, 1995 Hibernation is defined as a state of decreased inactivity and decreased metabolism (metabolism is what keeps you alive). Bears hibernate during the winter. Though it looks like they are sleeping, they are still breathing and their blood is still circulating. No animals in Antarctica really hibernate, but nematodes and tardigrades do something kind of similar. The difference is that they have NO metabolic activity when they "hibernate." This is called "cryptobiosis," and it lets these soil animals survive freezing temperatures and very dry conditions. When conditions improve, the animals can come out of this state and continue their lives. This "hibernation" can occur at any time and any place when conditions are bad. ******************************************* EMPEROR PENGUINS: TRAVELING DISTANCE ******************************************* __________ QUESTION: How far can an Emperor penguin travel in one day? ANSWER from Polly Penhale on January 12, 1995 This question is more complicated than it seems because Emperor penguins travel both horizontally and vertically. They both cover distance and they dive. A typical adult excursion from a colony is a feeding trip. On a typical day, an adult Emperor may travel a total of 120 km. About 3/4 of this is vertical diving and about 1/4 of this is horizontal distance across the ice. ANSWER from Michael Castellini on January 25, 1995 The traveling penguin question depends on a couple of things. If they are walking over the ice, then 10 miles a day would probably be pretty easy. If they are swimming, then it could be a lot farther. But, they may not have much reason to do this at most times of the year, for example, if they are tending their chicks. Then, they would go to sea and feed and come back. In those cases, they may go out 30-40 miles looking for food. ****************************************** SURVIVAL ****************************************** ********************* ANIMAL PROTECTION ********************* __________ QUESTION: How far away do you have to stay from the animals? Who makes sure that people follow the rules, and what punishments are there if they don't? ANSWER from Terry Trimingham on January 3, 1995 All of the animals here are protected under the Antarctic Treaty. Each country has its own way of upholding the Treaty. The United States implemented the Antarctic Conservation Act to conserve and protect the natural ecosystems and animals in Antarctica as our way of supporting the Antarctic Treaty. The National Science Foundation is the government agency with the authority to police the Antarctic Conservation Act. The NSF has designated a number of enforcement officers, and there is always one or more of them here at McMurdo to make sure that people abide by the rules. These enforcement officers will undergo investigations and provide reports to the NSF, and the NSF will use those reports to decide upon what punishment and/or action should be taken in the course of a violation. The Antarctic Conservation Act is punishable by up to $10,000 dollars in fines and one year imprisonment. Basically, if an animal alters its behavior in any way as a result of contact with humans, we consider those people to be in violation of the Antarctic Conservation Act. Many of the animals here seem quite "tame" as they do not have land predators. For example, Adelie penguins are quite curious and will come up and look at you if you are quiet and still. It is a special treat for us to see animals here, and we try to be very careful not to disturb them in any way. ********************************** SURVIVAL IN ANTARCTICA ********************************** __________ QUESTION: Since it hardly ever rains or snows in Antarctica, how do the animals survive? ANSWER: From Polly Penhale on February 3, 1995: Liquid water is required for life. Continental Antarctica is a desert like the Sahara, but it is cold, not hot. The Antarctic Peninsula region is not a desert. It has a maritime climate where it rains and snows. Animals and plants survive in deserts in many ways. In continental Antarctica, penguins eat snow for water. In certain mountains in the Dry Valleys near McMurdo, there are special sandstone rocks in which bacteria and microscopic plants actually live in the rock in between the sand grains. This microscopic life is described as "cryptoendolithic," which is a Latin word meaning "hidden (crypto)Ñinside (endo)Ñ lithic (rock)." These life forms live just under the surface of the rocks where they are protected from drying out, from extremely cold temperatures, and from too much light. In the Dry Valleys, there are permanently frozen lakes where bacteria and microscopic plants and animals live in the water under the ice cover. There are frozen streams leading into the lakes. For the few days of the year when the air temperature rises above freezing and the streams flow, there are mosses and algae. These plants are dried out and inactive most of the time, but begin to grow when the water flows. So, there are adaptations that allow plants and animals to live in Antarctica, but comparing this land to other places, there are few types of organisms that survive here. __________ QUESTION: Do the animals feel threatened having to share their territory with others? Is it right to interrupt their everyday lives, or are you interrupting their lives at all? Or do you basically just leave each other alone? ANSWER from Guy Gutheridge in February, 1995 The history of the interaction of people and animals in the Antarctic is dramatic. In the 1820s, people harvested so many seals for their skins that some seal species were almost wiped out. It would be hard to know if the animals were aware enough of the situation to feel threatened, but they certainly would have had every reason to feel that way. The same situation prevailed for the large whales during the 1920s and the 1930s. Now, Antarctica's animals are protected by international rules. For U.S. citizens in Antarctica, anyone who has not been issued a permit to work with the animals is not allowed to interfere with them at all. The penalty can be a fine of up to $10,000 and jail for up to a year. The seal populations have come back, and there is some preliminary evidence that the large whales are beginning a comeback. Everyday interactions between scientists (if they have been issued a permit) and seals or penguins are peaceful. Penguins show no fear of people and in fact will walk over to see what you are doing. A mother Weddell seal on the sea ice of McMurdo Sound does not get alarmed when a scientist puts a tag on the flipper of her brand-new pup. The instances of Antarctic animals having to share their territory with people are rare. Hallett Station, operated from 1957 to 1973, was in the middle of a penguin rookery, and the breeding populations of both penguins and skuas definitely were affected. Now, the site has been cleaned up (except for a large fuel tank), and the penguins have reoccupied their nesting sites. To set up a station today in a penguin rookery would be unthinkable. Another example of potentially harmful interaction was the French coastal Antarctic station Dumont d'Urville, which started building an airstrip that could have interfered with a penguin migration route. After a storm ruined the runway, the French decided not to rebuild it, partly for environmental reasons. The question of whether or not Antarctic animals are affected by the presence of humans is complex. One study of Adelie penguin populations near Palmer Station, Antarctica, showed a 13-percent decrease over the last two decades at Torgersen Island (site of frequent scientific and tourist activity) and a much larger 56-percent decrease at Litchfield Island (which is a Specially Protected Area that is rarely visited). The scientist in charge of the study concluded that the potentially adverse effects of tourism and research may be negligible relative to the effects imposed by long-term environmental changes. For an Antarctic penguin, death is never far away. Sea ice can interfere with access to the sea for food, blizzards often kill large numbers of chicks, and seals and skuas take their toll. These animals are tough. The wonder is that, despite the hostile natural environment, more penguins and flying birds live in Antarctica (350 million estimated) than people in the United States (about 260 million). Antarctic seals number in the tens of millions. These numbers far exceed the 4,000 scientists and support personnel and 8,000 or so tourists who visit Antarctica each summer. __________ QUESTION: How do seals and penguins get enough food? Is there enough sun for kelp to grow in the oceans there? ANSWER from Diane Stoecker on January 2, 1995 My group was studying plankton and algae in the ice. However, the plankton and algae from the ice are the base of the food web that supports fish, seals and penguins in Antarctica. In McMurdo sound, there are some seaweeds in shallow water. However, they are limited by sunlight because it is dark much of the year and because ice covers the water most of the time, reducing the amount of light getting to the bottom. In the Antarctic, especially far south like McMurdo, production by microscopic algae in the ice and in the water column is more important than production by seaweeds. ********************* WHAT DO BIRDS EAT? ********************* __________ QUESTION: How do birds in Antarctica get their food since there are not many animals or plants? ANSWER from Diane Stoecker on February 2, 1995 Most of the birds in Antarctica (all of them around McMurdo, which is far south) depend on the sea for their food. For example, the penguins dive for fish and zooplankton. The skuas catch small fish and squid at the sea surface. During the summer, they also prey on penguin chicks. On the Antarctic continent, there aren't any seed-eating or insect-eating birds like the ones we see around home.