What Is a Marine Mammal?

1 2 chapter 3 4 5 What Is a 6 7 8 Marine Mammal? 1 9 10 11 12 13 chapter outline 14 15 Characteristics of Mammals Exploring the Depths: International Union for Conservation of Nature 16 Mammalian Evolution Exploring the Depths: Sea Wolves and Sea Sheep? 17 Defining a Marine Mammal Exploring the Depths: Eurasian Otters: A Marine Mammal? 18 19 Quasi-Marine Mammals Exploring the Depths: Steller’s Sea Monkey: Were There More Species of Marine Mammals Historically? 20 Greater Bulldog Bat (Noctilio leporinus) Why Are Marine Mammals Special? 21 Fishing (or Fish-Eating) Bat (Myotis vivesi ) 22 Arctic Fox (Vulpes lagopus) Selected References and Further Reading 23 24 Before we embark on this book about the biology and In addition to hair, sweat, and mammary glands, mam- 25 conservation of marine mammals, we should first define mals also possess specialized teeth and, like birds, are en- 26 exactly what they are. Marine mammals are a diverse col- dothermic (or homeothermic, commonly referred to as 27 lection of species grouped together not because of a com- warm-blooded), metabolically generating their own heat 28 mon evolutionary history, but because they inhabit marine and maintaining a constant internal body temperature. 29 environments. Nevertheless, they are all mammals and as They also possess a four-chambered heart and their brain 30 such have many characteristics in common. has a neocortex (the outer part of the cerebral cortex that 31 is responsible for sensory perception, spatial awareness, 32 Characteristics of Mammals and “higher functions,” such as reasoning and language 33 skills). 34 Mammals (members of Class Mammalia) have several fea- 35 tures. They all possess hair composed of keratin, a protein; 36 three bones in their inner ear; and sweat glands. In females 37 some of these sweat glands have been modified to become 38 milk-producing mammary glands, or mammae, which give 39 this group of animals their name. Most mammals have teats 40 or nipples except for the monotremes (Subclass Proto 41 theria, Order Monotremata), which exude milk directly 42 from their pores to be lapped up by their young. The mono- 43 tremes, which include the echidna, or spiny anteater, and 44 the aquatic platypus (Figure 1.1) are also unusual in that they 45 lay eggs, unlike the rest of the mammals (Subclass Theria), 46 which produce live young. The monotremes also have a 47 common cloaca, or orifice, through which they lay eggs, 48 urinate, and defecate. These remaining (Theria) mammals 49 are separated into the Metatheria, which include the marsu 50 pials, and the Eutheria, or placental mammals. All marine Figure 1.1 A member of the mammalian order Monotremata, 51 mammals are members of the Eutheria. the platypus. 52 L

83440_CH01_Parsons_v3.indd 1 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

2 chapter 1: What Is a Marine Mammal?

1 2

Eocene Miocene Pliocene Recent Oligocene Cretaceous Paleocene 3 Pleistocene –

4 Sirenia 5 Hyracoidea Proboscidea 6 7 Artiodactyla 8 9 Cetacea 10 Perissodactylala

11 Tubulidentataa 12 Pinnepedia 13 Carnivora 14 15 16 Chiroptera 17 Insectivora

18 Dermoptera

19 Primates 20

21 Rodentia 22 23 Lagomorpha 24 Pholidota 25 Edentata 26 Marsupialia 27 Multituberculata 28 Monotremata 29 30 A 31

32 Pakicetidae 33 Pakicetus 34 35 Ambulocetidae 36 Ambulocetus 37 38 Remingtonocetidae 39 Dahlanistes 40 41 Protocetidae

42 Rhodocetus 43 44 Basilosauridae

45 Basilosaurus 46 47 48 49 Mysticeti 50 51 52 B Odontoceti L Figure 1.2 (A) A timeline showing mammalian evolution and (B) the sequence of evolution of various cetacean groups.

83440_CH01_Parsons_v3.indd 2 Achorn International 03/09/2012 01:33PM 83440_CH01_Parsons_v3.indd 3 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

chapter 1: What Is a Marine Mammal? 3

Mammalian Evolution 1 2 The evolution of the mammals really begins in the middle 3 of the Permian period (299–251 million years ago) (Fig- 4 ure 1.2) when reptile-like therapsids were one of the main 5 land-based predators. These creatures had several features 6 in common, including similar skull structures and incisor 7 teeth that were equal in size. A therapsid group that arose 8 in the late Permian period was the cynodonts (Figure 1.3), Figure 1.3 An artist’s impression of how a cynodont could have 9 animals with even more specialized teeth, including rear appeared. 10 teeth that had crowns roughly resembling those of molar 11 teeth. They also had a bony palate in the roof of the mouth 12 that separated the mouth from their airways, so they could 13 the wolves and cats (Order Carnivora), even-toed hoofed eat and breathe at the same time. Bones in their jaw also 14 mammals such as deer, cows, and hippos (Order Artiodac- transformed, with two of the smaller jaw bones migrating 15 tyla), odd-toed horses (Order Perissodactyla), the elephants to become the inner ear bones, presumably giving better 16 (Order Proboscidea), the flying bats (Order Chiroptera), to hearing capabilities. It is hard to say to what extent or when 17 the fully marine manatees and dugongs (Order Sirenia) and these animals developed hair. 18 whales and dolphins (Order Cetacea), and to monkeys, apes, A mass extinction approximately 251 million years ago 19 and humans (Order Primates) (Figure 1.4). at the end of the Permian devastated terrestrial life, with 20 approximately 70% of land vertebrate species going extinct. Domain Eukarya 21 During the succeeding Triassic (251–199 million years ago) Kingdom Animalia 22 and Jurassic (199–145.5 million years ago) periods, the ar- Phylum Chordata 23 chosaurs (i.e., dinosaurs and crocodilians) overtook the Subphylum Vertebrata 24 therapsids as the dominant land predators and the proto- Superclass Tetrapoda 25 mammals appear to have shifted into a different ecological Class Mammalia 26 niche, becoming smaller, primarily nocturnal, and prob- 27 ably insectivorous, rodent-like creatures. This new niche 28 may have led to further adaptations, such as hair to keep 29 warm, improved hearing, and a higher metabolic rate. The Defining a Marine Mammal 30 first true mammals appeared in the early Jurassic, with the What is the definition of a marine mammal? In Marine 31 first marsupial, and possibly eutherians, appearing later in Mammals of the World, Systematics and Distribution (1998), 32 the fossil record at about 125 million years ago. Dale Rice lists marine mammals as sirenians (manatees 33 At the end of the Cretaceous period (145.5–65.5 mil- and dugongs), pinnipeds (seals, sea lions, and walruses), 34 lion years ago) another extinction event wiped out many of and cetaceans (whales, dolphins, and porpoises). He also 35 the land and sea reptiles, including most of the (nonbird) notes several species of bats and carnivores that inhabit 36 dinosaurs. Mammals are then believed to have expanded marine waters and are sometimes considered to be marine 37 and diversified, particularly in the Eocene (55.8–33.9 mil- mammals, although he does not specifically define what a 38 lion years ago). Recent molecular studies confirm a peak marine mammal is. These groups include the bulldog (Noc- 39 in diversification at about 50 million years ago. However, tilio leporinus) and fishing bats (Myotis vivesi), the polar 40 they also suggest a (larger) peak in mammalian diversifica- bear (Ursus maritimus), the Arctic fox (Vulpes lagopus), and 41 tion between 100 and 85 million years ago, producing most several otters, including the sea otter (Enhydra lutris), ma- 42 current mammalian orders by around 75 million years ago, rine otter (Lutra felina), and Eurasian otter (Lutra lutra). 43 thus before the late Cretaceous extinction. Reynolds et al. (1999, p.1) describe marine mammals as 44 There are approximately 5,400 species of mammals follows: 45 ranging in size from the tiny Kitti’s hog-nosed (or bumble- 46 bee) bat (Craseonycteris thonglongyai ) and Etruscan shrew (a) “occupy or rely on aquatic, if not strictly marine, 47 (Suncus etruscus), which weigh little more than a couple of habitats”; 48 grams, to the blue whale (Balaenoptera musculus), which (b) “have evolved similar anatomical features, 49 is believed to be the largest animal that has ever lived (see including large body size, streamlined shape 50 Chapter 11). Mammals range from mouse-like rodents (compared to terrestrial relatives), insulation in 51 (Order Rodentia) and shrews (Order Soricomorpha) to the form of blubber and dense fur, and in most 52 L

4 chapter 1: What Is a Marine Mammal?

1 2 3 4 5 6 7 8 9 10 11 12 13 A B 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 C D E 29 Figure 1.4 Examples of the diverse range of animals contained in Class Mammalia. (A) Etruscan shrew; (B) hippopotamus; (C) giraffe; (D) elephant; (E) orangutan. 30 31 32 33 34 35 cases, a modified appendicular skeleton resulting 36 in reduction in the size of appendages”; and 37 (c) “possess some similar physiological adaptations 38 (e.g., for diving, thermoregulation, 39 osmoregulation, communication, and 40 orientation).” 41 42 They consider sirenians, pinnipeds, cetaceans, polar bears, 43 and also marine otters and sea otters to be marine mam- 44 mals but do not include species such as the North Ameri- 45 can river otter (Lontra canadensis) or the bulldog or fishing 46 bats. They do note, however, that these animals can be de- 47 pendent, at least in part, on the marine ecosystem. They 48 then go on to say that this classification is influenced by 49 the species listed under the U.S. Marine Mammal Protec- 50 tion Act (MMPA) of 1972, which states, “The term ‘marine 51 mammal’ means any mammal which (a) is morphologi- Figure 1.5 The polar bear, a species that is considered to be a 52 cally adapted to the marine environment (including sea marine mammal under the U.S. Marine Mammal Protection Act. L

83440_CH01_Parsons_v3.indd 4 Achorn International 03/09/2012 01:33PM 83440_CH01_Parsons_v3.indd 5 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

chapter 1: What Is a Marine Mammal? 5

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Figure 1.6 A sea otter eating crustaceans. 23 24 25 26 27 otters and members of the orders Sirenia, Pinnipedia and unusually long feet and claws, which aid them in their fish 28 Cetacea), or (b) primarily inhabits the marine environ- ing behavior. The species is found in forests and mangrove 29 ment (such as the polar bear)” (Section 3 [6]). However, swamps in Central and South America from Mexico to 30 this legally based definition of a marine mammal does not Argentina, but they are also found in Trinidad and the 31 specifically exclude bats or the Arctic fox, which may indeed Antilles. 32 primarily inhabit the marine environment. They hunt both freshwater and saltwater fish (as many 33 Many marine mammal field guides use similar clas- as 30 a night) using echolocation. The bat’s large wings en- 34 sifications, typically including polar bears and the sea and able it to glide over the water when hunting for fish. They 35 marine otters. Therefore, for the purposes of this textbook fly close to the water surface and trail their claws into the 36 pinnipeds, sirenians, and cetaceans are the main marine water. The claws and toes are laterally flattened, which re- 37 mammal groups described, but we also consider that sea duces drag and allows them to slice through the water. After 38 otters, marine otters (see Chapter 7), and polar bears (see catching a fish with their feet, the bulldog bat transfers the 39 Chapter 6) should be treated as marine mammals and de- fish up into its mouth. When the bat lands it chews up the 40 vote entire chapters to them (Figures 1.5 and 1.6). However, fish, breaking it into large pieces. The pieces are stored in 41 we briefly discuss some of the quasi-marine mammals cheek pouches and chewed again before being swallowed. 42 here. Their diet exposes them to the threat of water pollution 43 and makes them vulnerable to variations in water quality 44 on prey abundance and distribution due to the changing 45 Quasi-Marine Mammals climate, the alteration of freshwater influx as a result of 46 human water usage, or increased turbidity (i.e., reduced 47 Greater Bulldog Bat (Noctilio leporinus) clarity) associated with deforestation and other coastal and 48 Bulldog bats have large cheek pouches, in which they store inshore activities. There are also reports that fish farmers 49 food, giving them their name (Figures 1.7A). They are about in Guatemala kill this species, presumably due to their per- 50 7 to 14 cm long and weigh up to 75 g, with reddish brown ceived impact on profits, but their population status is not 51 fur on their bodies. They have relatively large wings and known at this time. 52 L

6 chapter 1: What Is a Marine Mammal?

1 2 3 Isla Angel 4 de la Guarda 5 Isla 6 B Tiburón 7 A J 8 A

9 C MEXICO A 10 L I 11 F O 12 R 13 N I 14 A 15 A 16 17 18 19 Pacific 20 Ocean 21 22 Figure 1.8 Map showing the current, known distribution of the 23 fishing bat. Data from: IUCN Red List. 24 25 26 Because of its limited distribution, small population 27 size, and risks of habitat destruction and degradation, the 28 fishing bat is listed by the International Union for Conser- 29 vation of Nature (IUCN) as “vulnerable” (see Chapter 17). 30 Invasive species, such as rats and cats, are also thought to 31 B Figure 1.7 Quasi-marine mammals. (A) a greater bulldog bat; be a concern for this species. 32 (B) a fish-eating bat. 33 Arctic Fox (Vulpes lagopus) 34 As its name suggests, this species of fox is found in the 35 northern polar regions, from northern Scandinavia and 36 Russia to northern Canada, Alaska, and even the islands of 37 Fishing (or Fish-Eating) Bat (Myotis vivesi ) Svalbard, Iceland, and Greenland. 38 Like the greater bulldog bat above, the fishing bat (Figure 39 1.7B) has relatively large wings and long, laterally com- 40 pressed claws that it uses to fish for crustaceans and small 41 fish, in a similar method to that used by the bulldog bat. 42 It has brown fur, with a paler underside, and weighs about Exploring the Depths: International Union 43 25 g. It has a very limited distribution, being found only for Conservation of Nature 44 on the islands and coastal areas on either side of the Sea of The IUCN includes governments as well as environmental 45 Cortez and on the central western coast of the Baja Califor- and animal welfare nongovernmental organizations. A ma- 46 nia peninsula (Figure 1.8). Because both the terrestrial and jor activity of the IUCN is the collation of the Red List of 47 marine environments it inhabits are effectively arid, the bat Threatened Species. This list categorizes species of animals 48 has a modified urinary system, which is an adaptation to and plants according to their conservation status based on 49 low water availability. This makes the fishing bat somewhat scientific information on species abundance trends, distribu- 50 more adapted to a marine environment than the greater tion, and threats. The IUCN Red List categories include, in order of species threat, “vulnerable,” “endangered,” and 51 bulldog bat. The fishing bat has also been seen up to 8 km “critically endangered” (see Chapter 17). 52 from the shore. L

83440_CH01_Parsons_v3.indd 6 Achorn International 03/09/2012 01:33PM 83440_CH01_Parsons_v3.indd 7 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

chapter 1: What Is a Marine Mammal? 7

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Figure 1.9 An Arctic fox. 25 26 27 28 The Arctic fox is about 85 cm long and weighs 3 to food can come from marine sources, such as scavenged 29 3.5 kg, with males being slightly larger (Figure 1.9). They are seal carcasses. Changes in marine productivity can there- 30 famous for their thick white coats of dense hair that provide fore greatly affect Arctic fox populations when lemming 31 camouflage in the Arctic snow and ice and insulation in one numbers are low. 32 of the coldest regions on earth. During the summer their The IUCN categorizes the Arctic fox as “Least Con- 33 coat changes color to brown, blending in with the tundra. cern,” meaning their survival as a species is reasonably se- 34 Pups are likewise born with a brown coat. cure. However, several populations are severely depleted 35 Further adaptations to a polar environment include and threatened, including the Scandinavian (Norway, 36 fur on the pads of their paws to insulate against heat loss; a Sweden, and Finland) population comprising an esti- 37 substantive fat layer, a typical feature of marine mammals; mated 140 adult Arctic foxes. This is primarily the result 38 a countercurrent system (see Chapter 4) that reduces heat of a long history of being hunted for their fur, despite the 39 loss from their extremities; and rounded and small extremi- legal protections the species has in these countries. The 40 ties (ears and muzzle), reducing the surface area through population on and around Medny Island (Commander 41 which they can lose heat to the environment (see Chapter Islands, Russia) has also been severely depleted as the 42 4 for an explanation of adaptations to cold temperatures). result of an outbreak of mange that stemmed from the 43 Indeed, many of their adaptations are similar to those of introduction of ticks from dogs brought to the island by 44 polar bears (see Chapter 6). Also similar to polar bears, the humans. The current population is only approximately 45 Arctic fox will walk on ice to find prey and may jump on ice 90 animals. 46 and snow to break the crust and gain access to prey hiding Historically, the Arctic fox faced competition from 47 beneath the snow. They may even eat seals and cetaceans by wolves (Canis lupus), but as wolf populations were depleted 48 scavenging from carcasses of stranded animals or animals by humans this competition has decreased. Instead, they 49 killed by polar bears. now compete with red foxes (Vulpes vulpes), whose ranges 50 Their main prey are lemmings (Dicrostonyx richard- are expanding, perhaps also due to the decline in wolf 51 soni), but when these are scarce up to two-thirds of their populations. Climate change as well as reduced available 52 L

8 chapter 1: What Is a Marine Mammal?

1 2 Exploring the Depths: Sea Wolves and Sea Sheep? 3 Although gray wolves (Canis lupus) are terrestrial mammals, An analogous case could be made for a breed of sheep 4 there is a population of wolves on the coast of British Colum- (Ovis aries) that live on the remote island of North Ronaldsay 5 bia, Canada and Alaska that occupy coastal habitats, with sub- in the Orkney Islands, Scotland (Figure B1.2). This semiferal 6 populations inhabiting the outer islands of this region. These flock lives almost entirely on seaweed for most of the year 7 wolves have been found to have a diet that is predominantly (except for the lambing period). They have been kept this way 8 (75%) marine based, consisting mainly of salmon and marine for almost 180 years when a dry-stone wall was built to ex- mammal carcasses (Figure B1.1). Their dependence on a marine clude sheep from the center of the island. During this time the 9 diet makes them vulnerable to impact from marine threats digestive physiology of this breed evolved to efficiently extract 10 such as oil spills and over-fishing of marine species. Should this nutrients and sugars from Laminaria species. The behavior of 11 population of “sea wolves” be considered marine mammals the sheep has also adapted to the availability of seaweed with 12 for conservation and management purposes? grazing linked to the tidal cycle and rumination generally occur- 13 ring at high tide rather than at night as in other sheep. 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Figure B1.1 A marine environment-inhabiting gray wolf from Figure B1.2 A marine environment-inhabiting sheep from 30 British Columbia. North Ronaldsay, Scotland. 31 32 33 Exploring the Depths: Eurasian Otters: A Marine Mammal? 34 35 The Eurasian otter (Lutra lutra) is widespread along Scotland’s bycatch and marine pollution (i.e., threats in common with 36 north and west coast (Figure B1.3). Its distribution is closely as- other marine species such as cetaceans and pinnipeds) do 37 sociated with coastal freshwater pools and streams because influence these populations, and therefore national agencies 38 otters use fresh water to wash salt from their fur to maintain should include these mammals for conservation and manage- its insulation. For this reason coastal Eurasian otters are gener- ment purposes. 39 ally considered to be terrestrial rather than marine mammals. 40 Based on their diet and behavior we should probably recognize 41 these populations as marine ecotypes because they feed on 42 small bottom-dwelling fish and crustaceans within the littoral 43 and sublittoral zones. Their feeding behavior is mainly diurnal 44 (in contrast to otters in fresh water, which are crepuscular (active during twilight) and nocturnal), which is an adaptation to 45 optimize foraging success when prey are least active and eas- 46 ier to catch. Furthermore, DNA analysis of otters has revealed 47 that some island populations such as those in the Orkney and 48 Shetland Isles are genetically distinct from Scottish mainland 49 populations. Whether a species is marine or terrestrial has relevance 50 for conservation and management. Scottish marine-dwelling 51 otters have been excluded in discussions on marine biodiver- 52 sity conservation and have not been included in national ma- Figure B1.3 A marine environment-inhabiting European otter L rine stranding recording schemes. Factors such as fisheries in a Scottish sea loch.

83440_CH01_Parsons_v3.indd 8 Achorn International 03/09/2012 01:33PM 83440_CH01_Parsons_v3.indd 9 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

chapter 1: What Is a Marine Mammal? 9

1 Exploring the Depths: Steller’s Sea Monkey: Were There More Species of Marine Mammals 2 Historically? 3 4 Two species of marine mammal were discovered and first de- Steller had his “cossack” shoot at it several times. The first scribed to science in the 18th century by the naturalist Georg shot missed. The second shot may have wounded the animal 5 Wilhelm Steller: Steller’s sea cow (Hydrodamalis gigas) and the and it disappeared. “However, it was seen at various times in 6 Steller sea lion (Eumetopias jubatus) (see Chapters 8 and 16, different parts of the sea” (Steller 1988, p. 83). 7 respectively). However, two other marine animals that Steller The naturalist Stejneger details an account by Tilesius that 8 describes in his writings remain a mystery to science. The first describes an animal which sounds remarkably like Steller’s sea 9 is the sea wolf, and Steller describes it as follows: ape. Tilesius named it Phoca mimica, which is an older name for the Northern fur seal. Steller was an excellent observer, but 10 There is another large marine mammal which resembles it is very difficult to observe animals in the sea when one is re- 11 the whale but is smaller, with a proportionately ally a land-trained naturalist. Stejneger also states that Steller 12 much thinner circumference. The Russians call had not seen a fur seal, either living or dead, when he made the it “sea wolf”; the Itelmen call it plebun; on the 13 detailed observation of the sea ape. It is, however, interesting Kamchatka River this animal is called tsheshshak. 14 to note that Steller makes no mention of the sea ape and the I have not been fortunate enough to see it during 15 resemblance it had to a fur seal in his book De Bestiis Marinis. my stay here. Only its meat, cheeks [jaws], tongue, It seems as though an observer of Steller’s caliber would have 16 and intestines are used for food. The fat is used made that connection. Most scientists agree that Steller saw 17 only as fuel in lamps and not eaten because, like something but what it was remains a mystery. 18 mercury, as soon as it is ingested, it comes out Perhaps science will never know what Steller described in again at the other end, and so the Itelmen only eat 19 these few lines. It is important to note that Steller was a great it when they are badly constipated or, just for fun, 20 observer, an extremely accomplished naturalist and wildlife ex- give it to others who do not know about it (Steller pert, who recorded biological information with great precision 21 2003, pp. 79–80). and detail. Perhaps what he saw was a previously unknown 22 The second is the sea monkey or sea ape. The famous species of marine mammal that did not survive until today and 23 19th century biologist, Leonhard Stejneger, who conducted is now extinct! 24 ground-breaking research on marine mammals and who also 25 wrote a book on Georg Steller, assumed the animal Steller 26 sighted was a sea lion (Stejneger 1936, p. 280). Steller describes the animal meticulously: 27 28 “On August 10, we saw a very unusual and new animal, 29 about which I shall write a short description since I watched it for two whole hours. The animal was 30 about 2 ells long (1 ell = 1.378 ft). The head was 31 like a dog’s head, the ears pointed and erect, and 32 on the upper and lower lips on both sides whiskers 33 hung down which made him look like a Chinaman. 34 The eyes were large. The body was longish, round, and fat, but gradually became thinner towards the 35 tail; the skin was covered thickly with hair, gray on 36 the back, russet white on the belly, but in the water 37 it seemed to be entirely red and cow-colored. The 38 tail, which was equipped with fins, was divided 39 equally into two parts, the upper fin being two times as long as the lower one, just like on the –Contributing author, Lorelei Crerar, George 40 sharks” (Steller 1988, p. 82). Mason University. 41 42 43 habitat and prey species are expected to further increase First, marine mammals are unusual because air- 44 competition between Arctic and red foxes. breathing animals in the ocean are a rarity. They are also 45 (for the most part) unique within mammals due to their 46 Why Are Marine Mammals Special? different appearance and morphology. This is particu- 47 larly true for cetaceans, which were considered to be fish 48 The question of why marine mammals are special has be- throughout the world even late into the 19th century. In 49 come an important one in recent years. Why are they often fact, an 1818 trial over taxation of fish oil in New York 50 singled out for protection over, say, marine turtles? And State (vs. the lack of taxation on whale oil) explored the 51 why should commercial whaling not be allowed to resume taxonomy of the whale. Ultimately, the jury declared the 52 in species that seem to have recovered in number? whale to be a fish in line with popular (and biblically seated) L

10 chapter 1: What Is a Marine Mammal?

1 opinion. Similarly, whales (like sturgeon) were declared to known examples being sea otters. When sea otters are re- 2 be royal fish in England in the early 14th century, a legal moved from the kelp forest ecosystem, their sea urchin prey 3 status that is still maintained today. They thus enjoy the multiply, consuming kelp and denuding and destroying this 4 various protections of being the property of the monarch marine “forest” ecosystem (see Chapter 7). 5 (other European monarchies have also, at one time or an- Finally, marine mammals are special because we be- 6 other, made similar claims). lieve them to be. Societies around the world have always 7 Marine mammals are also culturally important to hu- been in awe of the whale or have depended on seals and 8 mans. Any visitor to western Canada or the northwestern sea lions, earning these animals a unique place in our col- 9 coast of the United States will see the images of killer whales lective hearts. The fact that tours specifically to see ma- 10 made famous by the Nootkan peoples. In New Zealand rine mammals, especially cetaceans, is a global industry 11 marine mammals have an important cultural role, most worth over a billion dollars (see Chapter 18 on marine 12 famously perhaps (thanks to the movie Whale Rider) the mammal tourism) indicates the extent of public inter- 13 Whangara people of eastern New Zealand, who tell of their est and fascination for these animals. This is one reason 14 legendary ancestor Paikea who rode on the back of a whale marine mammals are treated as conservation “flagship” 15 to New Zealand after his canoe sunk. Even in Europe marine or “umbrella” species. A “flagship” species is a charismatic 16 mammals feature as important components of traditional or iconic species with which people can identify, or be 17 cultures, for example, stories and songs of Selkies (shape- motivated by, to promote conservation in general (i.e., a 18 shifting seals who can turn into people) in Scotland. These rallying image). The Worldwide Fund for Nature (called 19 are just a few examples of the place of marine mammals in the World Wildlife Fund [WWF] in the U.S.) uses the 20 the history, traditions, and cultures of humans. image of a panda as its conservation flagship species, but 21 Some species of marine mammals, particularly the many other groups use marine mammals (e.g., the Inter- 22 bottlenose dolphin, have been shown to be highly intel- national Fund for Animal Welfare uses a seal pup in their 23 ligent. Common bottlenose dolphins are part of the small, logo). 24 but growing, number of animals that demonstrate a degree The use of marine mammals as an “umbrella” species 25 of self-awareness (see Chapter 12). They appear to have is a subtly different use of a charismatic or iconic animal. 26 “names” or signature whistles (see Chapter 4), understand People may not be so motivated to conserve a rare ben- 27 the linguistic rules of word order or syntax (see Chapter thic (seabed) habitat but may be more willing to support 28 12), and maximize the efficiency of their communication the conservation of marine mammals that use or rely on 29 in a similar way to humans, with their most often used com- that habitat. Therefore, by conserving the umbrella species, 30 municative elements being the shortest in their vocabulary. collaterally other (less charismatic but no less important) 31 In fact, they are the first species demonstrated to follow this species and habitats are protected. 32 law of brevity, which is one of the basic rules that define all Returning to the MMPA as our guide for what consti- 33 human languages. tutes a marine mammal, we can see that the U.S. Congress 34 Marine mammals are “keystone” species, meaning they subscribed to the view that marine mammals are special, 35 are species that are essential for the proper functioning of stating, “marine mammals have proven themselves to be 36 an ecosystem and which if depleted or removed lead to a resources of great international significance, esthetic and 37 significant alteration, or even collapse, of that ecosystem. recreational as well as economic, and it is the sense of the 38 Top predators such as sharks and many marine mammals Congress that they should be protected and encouraged to 39 are known to be keystone species, with one of the best develop to the greatest extent feasible.” 40 41 Selected References and Further Reading 42 43 Angerbjörn, A., Tannerfeldt, M., Bjärvall, A., Ericson, M., A., Gittleman, J.L. & Purvis, A. (2007). The delayed rise of 44 From, J., & Noren, E. (1995). Dynamics of the Arctic present-day mammals. Nature 446: 507–512. 45 fox population in Sweden. Annales Zoologici Fennici 32: Burnett, D.G. (2007). Trying Leviathan: The Nineteenth- 46 55–68. Century New York Court Case That Put the Whale on Trial 47 Arita, H., & Ortega, J. (1998). The Middle American bat fauna: and Challenged the Order of Nature. Princeton University 48 conservation in the Neotropical-Nearctic border. In: Press, New Jersey. Bat Biology and Conservation (Ed. T. Kunz & P. Racey), 49 Darimont, C.T., Paquet, P.C., & Reimchen, P.C. (2009). pp. 295–308. Smithsonian Institution Press, Washington, 50 Landscape heterogeneity and marine subsidy generate DC. extensive intrapopulation niche diversity in a large 51 Bininda-Emonds, O.R.P., Cardillo, M., Jones, K.E., MacPhee, terrestrial vertebrate. Journal of Animal Ecology 78: 52 R.D.E., Beck, R.M.D., Grenyer, R., Price, S. A., Vos Rutger, 126–133. L

83440_CH01_Parsons_v3.indd 10 Achorn International 03/09/2012 01:33PM 83440_CH01_Parsons_v3.indd 11 Achorn International 03/09/2012 01:33PM © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION

chapter 1: What Is a Marine Mammal? 11

Goltsman, M., Kruchenkova, E.P., & Macdonald, D.W. (1996). Rice, D.W. (1998). Marine Mammals of the World. Systematics 1 The Mednyi Arctic foxes: treating a population imperiled and Distribution. The Society for Marine Mammalogy 2 by disease. Oryx 30: 251–258. Special Publication 4. Society for Marine Mammalogy, 3 Kruuk, H. (2006). Otters: Ecology, Behaviour and Conservation. Lawrence, KS. 4 Oxford University Press, Oxford. Roth, J.D. (2003). Variability in marine resources affects arctic 5 McCafferty, D., & Parsons, E.C.M. (2011). Marine mammal fox population dynamics. Journal of Animal Ecology 72: 6 ecotypes: implications for otter conservation and 668–676. 7 management. Aquatic Mammals 37: 205-207. Scheffer , V. B. (1958). Seals, Sea Lions and Walruses: a Review 8 Moore, P.G. (2002). Mammals in intertidal and maritime of the Pinnipedia. Stanford University Press. 9 ecosystems: interactions, impacts and implications. Stejneger, L. (1936). Georg Wilhelm Steller: The Pioneer of 10 Oceanography and Marine Biology 40: 491–608. Alaskan Natural History. Harvard University Press, 11 Cambridge, MA. Paterson, I.W., & Coleman, C.D. (1982). Activity patterns 12 of seaweed-eating sheep on North Ronaldsay, Orkney. Steller, G. W. (Edited by O.W. Frost) (1988). Journal of a 13 Applied Animal Ethology 8: 137–146. Voyage with Bering, 1741–1742. Stanford University Press, 14 Stanford, CA. Reynolds, J.E., Odell D.K., & Rommel, S.A. (1999). Marine 15 mammals of the world. In: Biology of Marine Mammals Steller, G.W. (Edited by M.W. Falk) (2003). Steller’s History of 16 (Ed. J.E. Reynolds & S.A. Rommel), pp. 1–14. Smithsonian Kamchatka: Collected Information Concerning the History Institution Press, Washington, DC. of Kamchatka, Its Peoples, Their Manners, Names, Lifestyle, 17 18 Reynolds, J.E., Powell, J.A., & Taylor, C.R. (2009). Manatees, and Various Customary Practices. (Translated by M. Engel Trichechus manatus, T. senegalensis and T. inunguis. In: & K. Willmore). University of Alaska Press, Fairbanks, AK. 19 Encyclopedia of Marine Mammals (Ed. W.F. Perrin, B. Wilson, D.E., & Reeder, D.A.M. (2005). Mammal Species of the 20 Würsig & J.G.M. Thewissen), pp. 682–691. Academic World: A Taxonomic and Geographic Reference. The Johns 21 Press, San Diego. Hopkins University Press, Baltimore. 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 L

83440_CH01_Parsons_v3.indd 12 Achorn International 03/09/2012 01:33PM