Tuesday, June 10, 2008

GLORIOUS FAIRY WRASSE!

A large male Cirrhilabrus roseafascia - the redtripe fairy wrasse - displaying at a rival. Photo Scott W. Michael.

The splendid fairy wrasse is certainly worthy of its name! Scott W. Michael.

How about that for an amazing fairy wrasse! This is a large male Cirrhilabrus roseafascia Randall & Lubbock, 1982, which is known commonly as the redstripe, roseband or pink-banded fairy wrasse. It gets around 20 cm in length and is known from New Caledonia, Vanuatu, Tonga, Fiji, Samoa, Palau and the Philippines. (Most of those in the aquarium trade are coming from Vanuatu and Tonga.) This large, beautiful fairy wrasse is found on deep reef slopes and drop-offs. It has been reported from 30 to 113 m, although juveniles may occur at lesser depths. It is a spectacular display animal (as you can see from the photograph).

The redstripe fairy wrasse tends to acclimate readily, but may acclimate more quickly if housed in a deepwater reef or dimly lit aquarium. They are not particularly aggressive, but because they tend to be larger than most congeners, they are usually the dominant fairy wrasse in the tank. It is a good jumper. Mostly females and small to medium-sized males found in the trade. The large males are ostentatious! Male C. roseafascia tend to be pink overall with an orange line along the back, often with a yellow dorsal and anal fin. It is distinguished by close relatives by the pelvic fins, with have a blue and or black and blue patch. The male in the photo above is displaying toward another fish.

There is another, closely related form that sometimes comes into the aquarium trade. It is apparently undescribed and is commonly known as the splendid or pintail fairy wrasse (Cirrhilabrus sp.). It differs from C. roseafascia in that is has a lanceolate caudal fin (a pointed tail). This species is also known from the Izu and Ryuku Islands, Taiwan, and the Philippines and reaches a maximum length of 12 cm. It has been reported from deepwater (32 to 40 m).While it has been referred to as Cirrhilabrus cf. lanceolatus in the past (Kuiter 2002), it is no doubt a distinct species. It makes it into the aquarium trade on rare occasions and does well in captivity. I have seen it available at www.liveaquaria.com on rare occasions. In fact, the specimen in the photo above was in the tank of the manager of liveaquaria.com, my fish buddy, Kevin Kohen. You can regularly find C. roseafascia at this website (click on the link on the right side of the page), although large males are less frequently available.
Copyright (2008) Scott W. Michael

Monday, June 9, 2008

GRIZZLY OR BROWN BEAR?

This series of photos is intended to demonstrate just how variable the brown bear is in a single population - all of these bears were photographed last year in early August along the Katmai coast. A young adult brown bear is shown above (sex unknown). Photo by Scott W. Michael.

An adult female known as Ms. Hook (she had two spring cubs at this time). Photo by Scott W. Michael.

Queenie, an elderly sow. Photo by Scott W. Michael.

A young adult male. Photo by Scott W. Michael.

Adult boar named Mickey. Photo by Scott W. Michael.

A large boar (in his prime) dubbed Pythagoras. Photo by Scott W. Michael.

A very large, older boar. Dripping saliva is visible resulting from jaw injury. Scott W. Michael.

Although sporting some nicks and cuts, this boar is in his prime - this is Tank. Scott W. Michael.

Ursus arctos is one of the most revered and feared beasts on earth. This mammal has been given numerous appellations, including grizzly, brown, coastal brown, Alaska brown and Kodiak bear. As a neophyte to bear classification, I found myself very confused by the common vernacular, as well as the scientific nomenclature applied to this bruin. How many species or subspecies are there and do these common names represent disparate populations?

It turns out that all of these common names refer to a single species - Ursus arctos. Typically, the term brown bear (as well as coastal and Alaskan brown bear) is applied to U. arctos populations that live in coastal Alaska, while Kodiak bear is used for “brownie” populations that live in the Kodiak Island archipelago (this includes the islands of Kodiak, Afognak, and Shuyak). Grizzly is usually reserved for U. arctos populations in the interior of Alaska, in Canada and the lower 48 states. While you can call them whatever common name you wish, they are all Ursus arctos.

OK - HOW MANY SUBSPECIES?

So they all fall under the single binomial Ursus arctos - but are brown and grizzly bears different enough to warrant distinct subspecies status? And how about the Kodiak bear – doesn’t it represent a different subspecies? (OK, I know many of you are starting to suffer from brain fog because of taxonomic overload, but I enjoy this stuff, so bear with me!)

Traditionally, subspecies have been defined as populations that differ slightly from one another, but that are not disparate enough to be elevated to the level of distinct species. In most cases, a subspecies represents a group of individuals that has been isolated from the main population long enough to exhibit some degree of change, but yet if they breed with members of the original population they will still produce viable offspring.

There has been much debate about how many subspecies of U. arctos actually exist in North America. In the early twentieth century (1918 to be exact) it was proposed that there were 86 subspecies of U. arctos in North America alone! This classification scheme was soon shot to pieces by the taxonomically-inclined, leading bruin biologists to recognize only two subspecies: the mainland populations, which were recognized as Ursus arctos horribilis, and the bear population of the Kodiak Island archipelago, which were referred to as U. a. middendorffi.

So, everything appeared to be as clear as mud until DNA analysis came on the scene. DNA has a biochemical signature that enables scientists to distinguish species and study their degree of relatedness. Recently, using mitochondrial DNA, researchers struck a body blow to the widely accepted North American-Ursus arctos classification scheme. These molecular surveys indicate that there is actually only one subspecies of brown bear in all of North America – this subspecies should be called Ursus arctos arctos (no more horribilis or middendorffi).

In a nutshell, this means that the grizzly bear, Kodiak bear and brown bear are all the same beast. It is a wide-ranging subspecies that does not only roam throughout North America, it is also found over much of Eurasia as well. That’s right, U. arctos arctos is a circum-global species, having been reported from the Balkans, Caucasus, Carpathians, Pyrenees, Italy (Abruzzo and the Benta Mountains), the Baltic States, Scandinavia (excluding Denmark), Greece, Syria, Russia and the countries of the Tibetan plateau (China, Tibet and Nepal). That said, there are a number of other valid subspecies on the European and Asian continents. (A side note: another very odd conclusion the molecule purveyors came to is that certain populations of brown bears are more closely related to the polar bear [Ursus maritimus] then they are to other brown bears! Now my head hurts!)

AMAZING VARIABILITY

While it may be that brown and grizzly bears are not distinct on the molecular level, some bear buffs still insist that the inland grizzly and coastal brown bears are different animals. There is no doubt, that some individuals from coastal regions do not look like their inland kin. A male coastal brown bear often has a more elongated neck, longer legs, and more protuberant face than its landlocked “cousin,” while inland boars are often more compact, with a shorter neck, shorter appendages and more concave face. But when it comes to physical appearances, there are no hard fast rules that can be consistently used to separate the coastal and inland populations.

This incredible variability in U. arctos populations is acutely demonstrated by the studies of Dr. Ian Sterling and Andrew DeRocher. These researchers examined a set of male U. arctos skulls from the Caucus Mountains, Russia. They noted that while some skulls looked like those of a “classic” brown bear, there was also a skull that resembled a panda (with short face and high profile) and another that looked more like a wolf cranium (i.e., it was more elongate and slender)!

Above, I mentioned that in 1918, a researcher described 86 different “species” of brown and grizzly bears in North America. Most of his research was based on the examination of skulls at the National Museum (sometimes only a single specimen of a particular “species”). Another researcher came-up with an even more elaborate classification scheme – he concluded that the skeletons of extinct and modern day brown bears he examined represented 232 distinct ursid species. In actual fact they all belonged to the highly variable U. arctos!

You only have to look at the photos of the brown bears in this blog (I have included a number of shots above) to see that most grizzlies do not look exactly alike. In fact, individuals are often so unique in appearance that bear-viewers regularly name them and readily recognize them from one year to the next. Some individuals have big ears; in others the ears are relatively petite. The bodies of some are long and lanky, while those of others are short and squat. Some have a long, prominent snout; others have the “classic” grizzly “dish” (concave) face. Some of these characteristics also change from spring to fall (e.g., bears get girthy as they pile on weight for the winter) and as the bears age (e.g., subadult males tend to be more gracile and finely built than males in their prime). The color of the pelage is not a constant either -there are blond, brunette, black furred and, on rare occasions, even white brown bears! In conclusion, while there may be differences between some individuals in coastal and inland population, you cannot consistently distinguish between the different populations.
Copyright (2008) Scott W. Michael

Saturday, June 7, 2008

DEEPWATER HOGFISH

A captive fivestripe hogfish smiles for the camera - actually, he is attacking his reflection in the aquarium glass! Photo by Scott W. Michael.

How about a cool hogfish – more exactly the fivestripe hogfish (Bodianus paraleucosticticus). It was recently described in a revision of the genus based on research done by Dr. Martin Gomon. This hogfish is a member of a group that includes a number of species which Gomon (2006) places in the subgenus Peneverreo. This includes three other species that tend to occur in deep water (usually depths of around 50 m or more) and have very scattered geographic distributions. The species in this subgenus all have narrow red or orange stripes along the body with a back spot on the base of the pectoral fin in juveniles and initial phase individuals.

It is a little known species that has been reported from Papua New Guinea, Bali, Palau, New Caledonia, Vanuatu, and the Cook Islands. It no doubt has a wider distribution than this, as it is a deepwater species that is just not captured or seen very often. Gomon (2006) reports that it occurs at depths of about 45 to at least 100 m (probably much deeper than this) on reef walls with numerous caves and ledges.

Very few of these fish have been imported for the aquarium trade. I have kept a single specimen which proved to be fairly hardy. It was quite frenetic when first added to the tank, dashing back and forth until it was so worn out it would stop, lay on its side for several minutes, and pant! It was not too aggressive and quickly learned to feed on frozen mysid shrimp. It was quite shy for some time, retreating to a cave or behind the rock work when there was activity near the tank. But after a while, it became more brazen. This B. paraleucosticticus would also display at and attack its reflection in the aquarium glass.

I would not add it to a tank with potential aggressors, like larger hogfish, other large wrasses, big damsels, or pugnacious triggerfishes. If my specimen was indicative of the species, they may hide constantly if they are picked on. Because it occurs at greater depths, it may prefer cooler water temperatures. I would suggest an optimal temperature range of 72 to 78 ยบ Fahrenheit. So, where do you get one? I was sent the specimen I kept from Kevin Kohen at www. liveaquaria.com (see link to the right) – that is only place I have seen this available.
Copyright (2008) Scott W. Michael

Friday, June 6, 2008

LOVE THEM LIOPROPOMA!

Check out this new Liopropoma sent to me by my fish buddy, Kevin Kohen at www.liveaquaria .com (go see the fish they have for sale by clicking the link on the right side of the page). At first I thought it was the pinstripe reef basslet (Liopropoma susumi), but after closer inspection I have concluded it may be something different. The nostril and head pore pattern (you can see them in the accompanying photo), the pectoral ray count (14 rather than the 15 or 16 present in L. susumi) and the color don’t quite match-up with the pinstripe reef basslet. According to Kev, my fish came from Indonesia. Like others in the genus, it is proving to be quite secretive, although he just arrived last night and is already coming out to accept mysid shrimp (he makes very quick forays into the open to snag the food items and then dashes back to cover). I am a huge fan of the reef basslets, although they are too secretive for some aquarists. To me, a fish that occasionally pops out to make its presence known (or at least to snap up a morsel), makes a fascinating and mysterious addition to the reef tank. Thanks for this one Kev!

(In a future post, I will present photos of some closely related Liopropoma to aid those interested in telling them apart.)
Copyright (2008) Scott W. Michael

BIRD FOOD (AVIAN-EATING BEARS)

Puffins on Ninagiak Island - brown bears will swim to the island from the Katmai coast in order to take exploit ground nesting sea birds. Photo by Scott W. Michael.

Birds are not staple fare in most grizzly bear diets. But being the opportunists that they are, these bruins will sometimes feed on the eggs and chicks of ground nesting birds. The first report of bird-eating I could find in the literature comes from a paper on the brown bears of Kamchatka (Bergman 1936). This naturalist reports that Russian U. arctos enter marshy areas before the salmon run to raid the nests of water fowl (i.e., “wild ducks”).

In a more recent reports, grizzlies in the Canadian Arctic Region (Tuktoyaktuk Peninsula) were observed eating the eggs of snow geese (Chen caerulescens) and adult ptarmigan (Lagopus spp.) (the latter is a rare event), while coastal brown bears, along the Katmai coast, have been observed capturing seagulls that were attempting to share a fish meal. In the “lower 48,” Gunther and Renkin (1989) observed Yellowstone grizzlies attempting to capture ducks (Anatidae), Canadian geese (Branta canadensis) and sandhill cranes (Grus canadensis). This occurred on rare occasions and the bears were never seen to successfully capture avian prey. Even so, there is no doubt that they do occasionally capture and eat these birds.

Campbell (1991) found that brown bears invaded the nests of the dusky Canada goose (Branta canadensis occidentalis) on the Copper River Delta, Alaska. About 50 % of the nests in this area succumb to predator activity and subadult and female brown bears with young were implicated in over half of all nests destroyed (males and solitary females rarely enter the nesting area). The bears would enter the nesting areas as soon as the geese began nesting until mid to late summer, at which time they moved to salmon streams.

Brown bears greatly impact the distribution of certain seabirds on the islands along the Katmai coast. Here, U. arctos has been observed swimming relatively long distances to gain access to ground nesting birds. For example, in Hallo Bay, Katmai National Park, brown bears will swim the 3.2 km (2 mi.) to Ninagiak Island to feed on the eggs of glaucous-winged gulls (Larus glaucescens) and puffins (Fratercula corniculata and F. cirrhata). Bailey and Faust (1984) reported the following at another island in the area:

“A sizeable tufted puffin colony…was destroyed by a brown bear. When we visited this island.. only about 100 puffins were milling about the grassy, burrow-ridden headlands, and a bear was systematically excavating burrows around the island’s perimeter. Entire slopes were dug up to the depths of nest chambers, and eggs shells and feathers were common.”

Puffins often nest in colonies. They dig burrows that are usually around 1 to 1.2 m (3 or 4 ft.) deep (there are reports of tufted puffins digging burrows as deep as 2.75 m [9 ft.]). In some areas, like Ninagiak Island, the burrows are dug on hillsides among scattered rocks and boulders. Brown bears use their long claws and massive shoulder muscles to displace rocks and earth in order to penetrate the nesting chamber. Both Alaskan species of puffin lay a single egg that hatches in 42 to 47 days. The chicks fledge for another 45 to 55 days, remaining in the burrow this entire time. While one parent takes care of the egg or chick, the other goes out to fish for food. Eggs and young puffins are available as bear food from at least June to August or September. On islands frequented by bears, puffins are rare.

Gull populations can also be impacted by the presence of coastal brown bears. Bailey and Faust (1984) report that gull nests were often found destroyed by bears and that bruins limit where these bird’s reproduce. They conclude that:

“The ubiquitous bears probably are largely responsible for the fact that fewer seabirds nest between Kamishak and Amber Bays than along any similar length of coastline on the Alaska Peninsula.”


The glaucous-winged gull, which is targeted by brown bears on Ninagiak Island, usually scrapes its nest in the ground and fills it with bits of grass, weed, moss, roots, twigs, turf, seaweed, etc. To give you some idea how profitable gulls can be as a food source for bears, consider this. Glaucous-winged gulls form nesting colonies which can number from 10 to as many as 10,000 pairs. Sometimes other gulls also form part of these large nesting aggregations. From 1 to 3 eggs are laid. They hatch in mid- to late June and are raised within the nesting territory.

During their study, Bailey and Faust (1984) observed 40 brown bears on or swimming between islands. They reported that many of these were sows and their cubs. It is advantageous for a mother bear to take her offspring to one of these offshore islands, not only because of the ready supply of “bird-food,” but also the island is likely to provide a safer refuge away from marauding male conspecifics. It is likely that cubs that were taken to an island by their mother, will return with their out young in time.

References:

Bailey, E. P. and N. H. Faust. 1984. Distribution and abundance of marine birds breeding between Amber and Kamishak Bays, Alaska, with notes on interactions with bears. Western Birds 15:161-174.

Campbell, B. H. 1991. Activities of Brown Bears on the Copper River Delta, Alaska and Their Impact on Nesting Dusky Canada Geese. Northwestern Naturalist, 72:92-99

Wednesday, June 4, 2008

COMING CLEAN ABOUT CLEANERS!

A Kidako moray (Gymnothorax kidako) sporitng a Labroides mustache! A young bluestreak cleaner wrasse works over the eel, grazing on slime and ectoparasites. But how do these wrasses do in captivity? Scott W. Michael.

The cleaner wrasse genus Labroides is comprised of five very species that rely almost entirely on cleaning to obtain nutrients as both juveniles and adults. Cleaning behavior is defined as a mutualistic relationship that exists between certain parasite-picking fishes and their piscine neighbors (the client or host species). The cleaner wrasse removes parasites, and also some slime and scales, from the client fish. This benefit to the client is that it hosts fewer annoying parasites.

Although the cleaner wrasses vary somewhat in their aquarium suitability, most members of this genus are considered difficult to maintain long-term in the home aquarium. There may be one exception to this – it is the bluestreak cleaner wrasse (Labroides dimidiatus). Although we have long considered it difficult to keep this species in North America, unless it was held with numerous fishes on which to “graze,” the Europeans consider it a good beginners fish! It is so popular there, that in 2002 it was one of the top ten species exported to the European Union. The Europeans report some encouraging longevity records. For example, the Nancy Aquarium, France has kept L. dimidiatus for over 11 years, while a lifespan of over six years has been reported to me by several European reef-keepers.

The biggest problem with the Labroides involves feeding. With the possible exception of L. dimidiatus, most species reject captive fare. As a result, they rely totally on the ectoparasites and slime present on their fish tankmates to meet their nutritional needs. This may not be as big of a problem if you have a large tank that has lots of potential clients, the cleaner wrasse may be able to acquire enough nutrients by grazing slime, and the occasional parasite. But if there is relatively little grazing surface (i.e., fish bodies), then the cleaner will not get enough food to stay alive. Not all potential hosts are as valuable a food source as others (that is, those species that produce more slime are more desirable). Therefore, the types of fishes you keep the cleaner with may impact its chances of survival as well. Those species of cleaner wrasses (e.g., L. phthirophagus) that rely heavily on fish slime as a nutrient source, will usually perish in quick order in most home aquariums. There is an occasional cleaner wrasse (usually individual L. dimidiatus) that will accept foods like finely chopped shrimp, mysid shrimp, frozen brine, freeze-dried tubifex worms, or even frozen prepared foods, and flake foods. One way to induce a finicky cleaner to feed is to present them with a live or fresh mussel that has had the valves forced open so that they can pick at the “meat” within.

Cleaner Wrasse Pros and Cons

Unfortunately for the aquarist, cleaner wrasses do not consume the most problematic aquarium parasites - the protozoa and dinoflagellates. Therefore, cleaners are not recommended as a means of biological control of for ich (Cryptocaryon irritans) or velvet (Amyloodinium ocellatum) outbreaks. But cleaner wrasses will control another group of parasites that frequently infect our fishes. It has been shown that the cleaning behavior of the bluestreak cleaner wrasse can reduce the number of the monogenetic flatworms (Benedenia lolo) in aquarium-held fishes. (Food choice studies have shown that when given a choice of four different foods [mucus, parasitic monogenean flatworms, gnathiid isopods, and a control] the bluestreak cleaner wrasse fed more on mucus and monogeneans.) While the L. dimidiatus did not eliminate all of the flatworms, they did help keep their numbers in check. There is also evidence that indicates these wrasses will pick off the cyst-phase of the flatworm (Paravortex sp.), which is commonly referred to as black ich (a.k.a. yellow tang disease). As a result, the Labroides spp. may also aid in controlling the outbreak of this ectoparasite in a closed system. Finally, bluestreak cleaner wrasse will remove the cauliflower-like growths associated with the viral infection Lymphocystis.

But adding a cleaner wrasse to a tank of fishes also has a downside. There are some “costs” associated with visiting a cleaner wrasse. The Labroides feed on host mucus, scales, and skin, especially when ectoparasites are in short supply. Because most of the parasites on the cleaners bill-of-fare are in short supply in the home aquarium, the captive Labroides will ingest larger quantities of fish slime and scales in order to survive. Because of a loss of its external protection, a “captive client” is likely to be more susceptible to bacterial infections and infections by protozoa and dinoflagellate parasites. It is only logical that a cleaner is going to be more of a menace in a smaller tank that contains fewer potential clients to feed off of. Therefore, if you are going to keep a Labroides, it would be wise to house it in a larger tank with a relatively large fish community. In a large tank it will also be easier for potential clients to avoid the attentions of a cleaner wrasse.

A client fish that gets nipped by a cheating Labroides may retaliate by chasing it off. This behavior is commonly seen in the aquarium and can be problematic for the cleaner, as certain tankmates may persistently attack it anytime it comes near. On rare occasions, a exasperated fish may turn on the cleaner and kill it. For example, triggerfishes have been known to dispatch an annoying cleaner wrasse. On the other hand, Labroides will sometimes hound less maneuverable species, like puffers, trunkfishes, and porcupinefishes, causing them great duress. This pestering may even elicit an Ostracion trunkfish to emit its deadly toxins and wipe out a whole captive community. A confused cleaner might persistently attempt to nip at and chase fishes with small spots. In some cases, it appears that the cleaner is attempting to feed on the “parasite-like” markings.

Copyright (2008) Scott W. Michael

GROLAR BEAR NEWS

News about the grolar bear - the grizzly - polar bear hybrid. Click here for more info.

Tuesday, June 3, 2008

JAW SLINGER! A NEW SPECIES OF EPIBULUS.

A male Epibulus brevis, the dwarf slingjaw wrasse, photographed in the Raja Ampat Islands, West Papua. Photo by Scott W. Michael.

The yellow color form of the female Epibulus brevis photographed in Lembeh Strait, Sulawesi. Note the black coloration on the pectoral fins. Photo by Scott W. Michael.

The brown color form of the female Epibulus brevis photographed in Lembeh Strait, Sulawesi. Note the yellow spot on the dorsum. Photo by Scott W. Michael.

The slingjaw wrasse (Epibulus insidiator) is a well known member of Indo-Pacific reef fish communities. It has also been recognized for some time that a strange, smaller slingjaw wrasse was lurking around coral reefs of the Western Pacific. (Some of us thought it was simply a color variant of E. insidiator.) It took ichthyologist, Dr. Bruce Carlson, to solve the Epibulus mystery, once and for all. Bruce, along with the god of reef fish taxonomy, Dr. John Randall, and molecular biologist, Michael Dawson, described Epibulus brevis, commonly known as the dwarf slingjaw wrasse, earlier this year.

Carlson et al. (2008) report E. brevis from Palau, the Philippines, Papua New Guinea, Solomon Islands, Sulawesi, Bali, Lombok, and Flores in Indonesia. I recently observed this fish in West Papua as well. It differs from E. insidiator in color. The males of this species are all brown with yellow on the throat area, on the caudal fin and a yellow marking at the opercular flap. Females vary in color from dark to light brown to yellow or almost white. The pectoral fins of the female almost always have black on the pectoral fins. The dwarf slingjaw also has longer pectoral fins than E. insidiator and there are also genetically distinct.

What is refreshing about this paper, is that it not only deals with taxonomy issues, but also compares the biology of the two known Epibulus spp. For example, the authors examined the stomach contents of both slingjaw species. The stomach contents of 20 E. brevis consisted mostly of crustaceans (crabs and shrimps), with only one larger individual (17.2 cm [6.8 in.]) containing both fishes and crabs. They also examined the “gut” contents of 31 E. insidiator and observed that the stomachs yielded more fish than E. brevis, but also crabs, shrimps, and polychaete worms. The authors suggest that the larger size of the E. insidiator may explain their proclivity to ingest more fish (likewise, smaller E. insidiator tended to contain more crustaceans than larger conspecifics). In both species, prey was highly masticated as a result of the actions of the pharyngeal teeth.

There are also some subtle differences between the behavior of the two species. Male E. insidiator will patrol high in the water column. When patrolling, the dorsal and anal fins are contracted, while the caudal fin is spread open extended. Most of male E. insidiator activity occurs over prominent reef features such as coral promontories and large boulders, which apparently serve as sites where the fish rendezvous with potential mates. Females hover or swim slowly about these sites and occasionally bob up and down as they move near a male. According to Colin and Bell (in Carlson et al. 2008), E. brevis spawns at sunset. Males do swim around a territory and occasionally rise into the water column, but they engage in less flagrant displays than E. insidiator and usually remain nearer the sea floor. When attempting to entice a female to spawn, a male E. brevis will swim around his potential mate with all his fins collapsed. However, the median fins are spread as the pair rise into the water column to spawn. There may even be differences in habitat preferences. Epibulus insidiator tends to occur in clear, outer reef habitats, while E. brevis is more common in protected areas.

There are many more reef fishes that have long been known to reef fish taxonomists that await formal descriptions. But, I for one, and very happy that the new Epibulus has finally been given a moniker.

References

Carlson, B. A., J. E. Randall, and M. N. Dawson. 2008. A New Species of Epibulus (Perciformes: Labridae) from the West Pacific. Copiea 2008 (2): 476-483.

Copyright (2008) Scott W. Michael

MALEVOLENT MOTHERS AND BRUIN BABYSITTING: PART 2

The brown bear sow (Ms. Hook) that trusted us to babysit her two spring cubs for approximately 20 minutes.



The spring cubs occasionally look back to observe us, but for the most part seemed completely comfortable with being "cached" with Homo sapiens. All photos by Scott W. Michael.

In the last bear post (click here to read), we looked at how mother bears will utilize the presence of human groups to increase their level of security while nursing their young – a indicator of their ability to learn and their behavioral plasticity. Last year (2007) in Katmai, our group was able to witness an even more amazing phenomenon, related to sows and dependent cubs. This behavior has been dubbed as “cub-caching.” During this behavior, instead of moving close to human groups to nurse, the sow will approach a hominid cluster with her cubs, and then leave her offspring with the humans while she goes off to fish among the other bears. That’s right, they employ our species to babysit their youngsters! Quite a contrast to the mother bear described in my last posting that attacked the two hikers in Glacier National Park, eh (click here)? Once again, the root cause is the fact that some large boars have an aversion to us and at least some sows have learned to take advantage of it. By leaving their young cubs near a group of people, the sows can go fish without putting their offspring at risk of being attacked by other bears.

During my stay at Katmai National Park, our group experienced cub caching on three separate occasions. Our first experience with this behavior went something like this: mother bear (dubbed Ms. Hook) came sauntering along a tributary that snaked from the river mouth to the sea, with two small shapes trotting along some distance behind her. The two cubs were lagging behind, occasionally stopping to sniff the sand and to pick-up bits of debris (e.g., shells) in their mouths. When the sow was adjacent to our little clump of humanity (about 4 m away) she stopped and waited for her kinder to catch-up. When they did, she abruptly vocalized and the two cubs plopped down on the wet sand. I assume the vocalization was their cue that we were in charge for while. Mother bear then proceeded to head for the prime fishing area, 60 to 80 yards further along and into the estuary, and join the other bears that were already chasing and jumping on their illusive quarry. So there we were, 3 to 4 m from two winsome spring cubs that were not at all concerned about the gawking band of two-legged, one-eyed anthropoids (that one- eye was the lenses protruding from the camera that are faces were pressed up against)! The cubs simply sat on their haunches and watched their mother leave, they turned to check us out, one laid back in repose, they checked out debris in the sand – in short, they were ideal little charges!

After five minutes or so, they moved along in front of us (much to the delight of the photographers as they had originally parked themselves between us and the sun) and sat down side-by-side with their backs facing us. They remained there until a big pulse of salmon entered the estuary mouth and all hell broke loose with the adult bears chasing fish in various directions. The sudden commotion startled the little bears, which ran past us and took up a position behind our group. They remained there for a little while longer until mom came back to pick them up.

I could not believe what I had just witnessed - I had read about it, but to actually see it happen was mind altering! To have this powerful, often misunderstood mother, entrust us with her seven month old offspring while she went off to catch her supper! The photos above were all shot during our first baby-sitting (cub-caching) encounter. That 20 minute period was worth the cost of the entire trip and was no doubt my most memorable wildlife encounter!

Copyright (2008) Scott W. Michael

Monday, June 2, 2008

UNARMED PERCHLET (PLECTRANTHIAS INERMIS)

Do you have an unarmed perchlet in your tank yet? WHAT ARE YOU WAITING FOR?? Photo by Scott W. Michael.

There are over 40 species in the genus, many of which would make fascinating aquarium inhabitants. This is one of the most spectacular members of the genus, Pelicer's perchlet (Plectranthias pelicieri). It is rarely collected and those specimens that are go to the Japanese ornamental fish trade. Photo by Tsuyoshi Kawamoto.

There are a number of fish species that have become quite common in the aquarium trade in the last six years. One of these, that I am most excited about, is an aberrant member of the subfamily Anthiinae. That’s right – it, and its kin (i.e., other members of the genus Plectranthias), are freaks of the subfamily. Most of the anthias spend the daylight hours in the water column, snapping up zooplanktors. But the freaky little perchlets behave more like hawkfishes (family Cirrhitidae) than their anthias relatives (so much is their likeness to a cirrhitid, that P. inermis is often sold in the aquarium hobby as the “geometric hawkfish.”) Rather than soaring about, high in the water column, they spend their time in repose on the seafloor. The are very cryptic, hiding among coral rubble or among stony coral branches during the day. These little fishes are often most active at dusk and dawn, or in dimly-lit microhabitats, like on rubble-covered cave bottoms or in the shadow of reef overhangs.

The unarmed perchlet (Plectranthias inermis) is a small fish, attaining about 5 cm in total length, that is ideal for the nano-reef aquarium. It is a threat to small ornamental shrimp (e.g., anemone shrimp), but otherwise, your prized invertebrates will be safe in the perchlet tank. It is also a threat to small gobies (e.g., Eviota, Trimma, Trimmatom). As far as its piscine neighbors are concerned, P. inermis is best housed with small, passive fish species (smaller cardinalfishes, small wrasses, blennies, dragonets, gobies, dartfishes). Its diminutive stature also means it a potential meal for large fish-eaters and a target of benthic bullies (e.g., dottybacks, hawkfishes).

More than one unarmed perchlet can be kept in a medium to large aquarium. However, males may fight (males, in general, are larger than females). Before making its approach toward a conspecific, P. inermis will raises and lower its elongated dorsal spine. If aggression escalates, the assailing perchlet will skim over the bottom as it approaches its adversary, with its tail slightly higher than its head. It undulates its tail, apparently to move itself forward, and spreads its gill covers (primarily the lower portion of the buccal area). All the fins are spread. I have noticed that as these fish grow, the pectoral fins become larger in proportion to the body size. Although studies are lacking, it is likely the Plectranthias spp. are protogynous hermaphrodites like other members of their subfamily.

The unarmed perchlet can be quite secretive, but will spend more time in the open in an aquarium that contains dither fish species such as Chromis, flasher wrasses, forktail blennies. It is prone to jumping, especially from tanks without adequate shelter and hiding places. Remember, is natural tendency is to lurk within rocky hiding places, resting at the entrance of a shelter and making a brief forays into the open. Provide it with nooks, crannies and caves.

This is the only member of the genus that I have encountered in the trade, although I continue to hunt!

Want a perchlet? Just click on the link below and go to the Diver's Den!

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Copyright (2008) Scott W. Michael

MALEVOLENT MOTHERS AND BRUIN BABYSITTING: PART 1

When sows nurse their young, they are placed in somewhat of a precarious position, having to recline on their back with back legs splayed forth. It turns out, some females will utilize groups of humans as a refuge as they engage in nursing. Photo by Scott W. Michael

“Hushai said moreover, "You know your father and his men, that they are mighty men, and they are fierce in their minds, like a bear robbed of her cubs in the field…” 2 Samuel 17:8

"Better to meet a bear robbed of her cubs than a fool in his folly." Proverbs 17:12

"I will meet them like a bear that is bereaved of her cubs, and will tear the covering of their heart." Hosea 13:8

The writers of old were well aware that it was not a good idea to threaten the young of a mother brown bear. Contemporary authors have rang the same warnings bells. If you read any guide on recreating in bear country, one of the ironclad rubrics is to never approach a grizzly sow with offspring. As we discussed in an earlier posting, mother grizzly is a product of her environment, which in the past, was not a very safe place to raise a family. So she will sometimes respond aggressively to a perceived threat - which people are, at least over some portions of the grizzly’s range.

Consider the case of Ann Quarterman and Christine Bialkowski described in the book Mark of the Grizzly. While this book is considered “bjorn porn” (bjorn is Norwegian for bear*) by many ursidophiles, the Quarterman and Bialkowski attack clearly demonstrates just how protective a mother bear can be. The two women were hiking in Glacier National Park, when they spotted a sow with two cubs of the year in tow some 300 meters away. The female, upon spotting the two hikers, immediately began charging toward them. The two girls jumped up and down and yelled hoping that the bear would recognize them as human and forestall her attack, but the sow kept coming. They finally ducked behind a rise so that they were out of sight of the agitated mother bear. She pressed on until she located the hikers cowering behind the ridge and subsequently mauled them both before running off with her offspring. (One woman had bear spray and actually unloaded the whole canister on the bear, but it apparently had little effect on the sow’s desire to do harm to the perceived threat to her cubs.)

There is no doubt that a mother grizzly can morph into one of the most ferocious animals on the planet, if she feels that her cubs are in peril. But momma bears, at least in some areas, do not always look at humans as a threat. Consider the refuging behavior employed by sows with dependent cubs. This was first described in the population of Ursus arctos that frequent the McNeil River Sanctuary. At McNeil, there is a viewing pad, where all human observers are to remain when watching the bears. Biologists began to notice that mothers with cubs would approach near to the viewing pad when they wanted to nurse their young. During the nursing process, the mother bear lies on her back and her progeny climb onto her belly and suckle at one of her six nipples (they may move from one nipple to another until mom’s milk supply is temporary exhausted). During this time, mother and babies are more vulnerable to attack. If other bears are around, the sow will keep a close eye on the goings-on of her neighbors. If she feels threatened, she will quickly jump to her feet, sending the cubs tumbling to earth, and prepare to defend her offspring.

It turns out (as I mentioned in the last post) that in many areas where bear-viewing occurs, large males tend to be more wary of human groups. (It has been suggested that boar avoidance of people is a function of their being more likely to have had negative experiences with hunters, who usually target large males.) You can see this avoidance behavior at McNeil River, where many larger boars remain on the side of the river opposite the viewing pad. OK –so here is where it gets real interesting. Female bears have learned about these tendencies and as a result, in order to increase their security levels during these nursing bouts, some sows will sidle-up to our kind! Is that not awesome - that mother brown bears have learned to use bear-viewers to help take care of her cubs.

That female’s take advantage of ecotourists has been studied in British Colombia (Nevin and Gilbert 2005). These researchers found that female’s with dependent cubs catch more fish-per-unit-effort when ecotourists are present than when they are not. They concluded that this increase in foraging effectiveness was due to the fact fewer males are present when bear-viewers are around. (Other studies in this region have shown that large boars tend to fish more at night when humans vacate the fishing area, while more mothers with cubs fish during the day.)

We will examine an even more incredible phenomenon, cub caching, in my next post.

References:

Nevin, O. T. and B. K. Gilbert. 2005. Measuring the cost of risk avoidance in brown bears: Further evidence of positive impacts of ecotourism. Biol. Conserv. 123:453-460.

video

Paula, a very experienced and defensive sow, nurses her yearling cub, Racer. After nursing, Racer relaxes and enjoys the security of having a good mom. Video by Scott W. Michael.

* - I borrowed the saying “bjorn porn” from bear biologist Steve Stringham - we will discuss Steve and his amazing work in a future post!


Copyright (2008) Scott W. Michael