The Purple Gallinule (Porphyrio martinica) sometimes referred to as a ‘swamp hen,’ is a brightly colored bird that can be found gracefully walking across floating vegetation in southern and tropical marshlands.
Purple Gallinules are chicken-sized birds that reach a mature length of approximately 14”, with a wingspan of 20” to 24”, and a mature weight of 7.3 oz. to 10.2 oz. They have red eyes, a short, triangular red bill with a yellow tip, and a light blue or white frontal shield (located on the forehead.) Some of their most unique features are their tall, thin yellow legs and long toes (used to navigate across floating vegetation.) PG’s are perhaps best known for their striking coloration. Purple-blue plumage covers the head, neck, breast, short tail, and underside. The back and wings are green-blue and their undertail coverts are white. Chicks are born covered in black down. Juveniles are buff to brown in color, with some green on their backs, yellow legs, and dull facial features.
Purple Gallinule movements on land have been likened to those of a chicken while in the water, they’re said to move like a duck. Their long toes enable then to gracefully move across floating vegetation, but make it difficult for them to clamber through dense shrubs.1 While walking or swimming, they move their head and tail in a constant jerking motion. The flight of the PG has been described as labored and slow, with dangling legs. Despite this, PG’s have been known to fly great distances from their home ranges and have been sighted as far north as southern Canada and Maine.
Purple Gallinules are vocal and make squawking, cackling, and guttural grunting noises.
PG’s can be found in freshwater marshes, wetlands, lakes, waterways, or bayous where there is a presence of floating vegetation (such as lily pads.)
They are year round residents of northern, central, and eastern-central South America, parts of Central America, southern Florida, and the Caribbean. Breeding ranges reach northward to Texas, Arkansas, the Carolinas, and the Gulf Coast. Some populations migrate short distances and winter along the Gulf Coast of the United States and in Central America.2 Although the PG is not a graceful flier, there have been sightings far from this species normal range (in the northern United States, southern Canada, Europe, and South Africa.)3
They are ground foragers whose diets consist of aquatic vegetation, grasses, seeds, fruit, water hyacinth flowers, grains, insects, and some invertebrates. They gather plant material while standing atop floating vegetation, climb brush for seeds or fruit, and collect insects off the bottom of lily pads (by rolling the edge over and holding it in place with their foot while collecting the insects with their bill.) Insects are fed to the chicks. PG’s are able to use their feet to hold food while eating.
Purple Gallinules breed between April and September. Nests are built using grasses and other aquatic vegetation and are attached to either a floating mat or a thicket of vegetation. Between 6 to 10 eggs are laid -one per day- that are creamy to buff with small irregular brown spots. Both the male and female incubate the eggs for 18 to 20 days. The chicks hatch over the course of 3 to 4 days, covered in black down. The chicks generally remain in the nest until all the eggs have hatched, but are able to leave the nest within a day of hatching if disturbed (already capable of swimming, diving, and running.) The chicks are fed by both parents for 8 to 9 weeks. By 7 weeks old, the chicks are capable of short flights and by 10 weeks old, they can make sustained flights (by this time the chicks have reached 1/3 their mature size.)4
Notes of Interest
There is a hunting season for PG’s in the United States; however, they are not a common game bird and by the time the season opens, local Purple Gallinule populations have often already started migrating south. For example, the hunting season in Arkansas includes a daily limit of 15 birds and lasts from September 1st through November 15th.5
Spiny Dogfish, Squalus acanthias, are small coastal sharks that can be found swimming in large packs. Their genus name translates as “a kind of sea-fish,” an appropriate fit for a species that can be found exclusively in seawater. Their species name is Latin for “a prickly thing,” referring to the characteristic spines found on their dorsal fins. The Spiny Dogfish is considered a vulnerable species by the IUCN due to a number of issues, including commercial fishing practices, the species’ advanced age at sexual maturity, and a long gestational period.
Spiny Dogfish are small coastal sharks. Females tend to be larger than males, reaching average mature lengths of 30” to 42”. Mature males measure 24” to 35” on average. Adult Spiny Dogfish weigh 6.5 to 20 lbs. The maximum recorded weight of a female was 21.6 lbs.1 Dogfish living in northern parts of their range tend to be larger on average than those in southern regions.2
Spiny Dogfish have a slate grey to brown dorsal surface and white or pale grey ventral surface. Immature fish have a row of small white spots on each side of their body that reaches from above their pectoral fins to above their pelvic fins. These spots usually fade away with maturity. The edges of the dorsal and caudal fins are pale in color at birth. Spiny Dogfish are covered in placoid scales that are similar in structure to teeth. Each scale terminates in a rear-pointing spine.
Spiny Dogfish have an elongated and slender appearance. Their long, pointed, flat snouts are lined with nearly continuous rows of small, flat, smooth teeth (28 upper and 22 to 24) with deeply notched cusps and oblique points that angle toward the corners of the mouth.3 They have large eyes and narrow anterior nasal flaps.
Spiny Dogfish have two dorsal fins, each with a prominent anterior spine that is mildly venomous. These spines are used as defense mechanisms. The second dorsal fin is approximately two-thirds the side of the first. The pectoral fins are triangular in shape, with curved margins and rounded rear tips.4 They control direction during swimming. The pelvic fins (which aid in stabilization along with the dorsal fins,) are located nearer to the second/rear dorsal fin than the first. Pectoral and pelvic fins are located on the sides of the body. Spiny Dogfish, like other Squaliform sharks, lack anal fins.5 The caudal peduncle has low lateral keels. The body of a Spiny Dogfish terminates in an asymmetrical caudal fin.
The name Dogfish came from fishermen who observed this species swimming in large “packs” chasing schools of smaller fish. Spiny Dogfish are gregarious and form schools of hundreds, or even thousands, of fish. These schools consist of fish of one sex that stay together as they grow (although small, immature males and females may be found in the same school.) Schools of immature fish are typically found offshore. Mature females usually school closer to shore.6
Female Spiny Dogfish reach sexual maturity at 18 to 21 years of age and can live to a maximum age of 40 years. Males reach sexual maturity by 11 years old and can live to a maximum age of 35 years.7 The advanced age of sexual maturity combined with a long gestational period make this species especially vulnerable to over-fishing.
Spiny Dogfish can be found on the continental shelf in shallow, northern inshore waters during the summer and deep, southern offshore waters in the winter. They inhabit temperate and boreal salt waters that are ideally 6° to 11°C. Although they prefer seawater, dogfish can tolerate brackish water.
Within their habitats, Spiny Dogfish are prey to by cod, goosefish, red hake, larger species of sharks including larger Spiny Dogfish, seals, and killer whales.
The Spiny Dogfish is an abundant species that can be found on the continental shelf in temperate and boreal waters around the world. They can be found as far north as Greenland, Iceland and the Bering Sea and as far south as Argentina, South Africa, Chile, and New Zealand8 at depths exceeding 2400’.9 The Spiny Dogfish is a highly migratory species whose movements are determined by water temperature. They move to inshore northern waters for the spring and summer and to deep, southern offshore waters for the winter.
Spiny Dogfish are voracious and opportunistic eaters that have become unpopular with fisherman due to their tendency to chew through commercial fishing nets, releasing and driving away schools of fish. They swim in predatory packs and attack schools of smaller fish. Their diets consist of deep-sea fish species including herring, mackerel, haddock, capelin, squid, jellyfish, octopus, smaller sharks and shark egg cases, shrimp, and crabs. Because of their slender appearances in the spring, it is believed that Spiny Dogfish rarely feed during winter months.10
Internal fertilization occurs in offshore waters during the winter months. Early on in development, the female’s body secretes thin, transparent, horny shells. Each shell, called a candle, surrounds several ova within the ovaducts.11 Litters may contain between 1 and 15 pups (but on average 6 to 7,) with an average male to female ration of 1:1. The embryos develop internally for 22 to 24 months, known as ovoviviparous development. This is the longest gestational period of any vertebrate. For the first 4 to 6 months of development, the embryos receive nourishment from surrounding membranes. After these membranes break down, the embryos no longer have a placental attachment and receive nourishment from yolk-sacs for the duration of the gestational period. The young, referred to as pups, are born offshore during the winter months. The pups are born headfirst, measuring 8” to 13” in length. Dorsal spines are present at birth. To protect the mother from being injured, the pups’ spines are covered in sheaths of cartilage during birth.12
Notes of interest
Spiny Dogfish are used to make oil and fish meal and are commonly used to make fish and chips.13
Spiny Dogfish may also be referred to as: Blue Dogs, Common Spinyfish, Grayfish, Rock Salmon, Spiky Dogs, Spur Dogs, and White-spotted Spurdogs.14
Spiny Dogfish are caught with longline, troll, trawl, sink gill nets, and jig handline gear.15
Spiny Dogfish are a popular species in the commercial fishing industry. The industry experienced a peak in 1974 when 27,400 metric tons collected. This was followed by a sharp decline in the 1980’s, when only 5900 metric tons were collected. Commercial fishing of this species regained its strength in the 1990’s and in 1996 over 28,000 metric tons were collected.16
The American Marten, Martes Americana, also know as the pine marten, is a member of the mustelid family, related to badgers, weasels, mink and otters. They are small, slender mammals known for their soft, shiny coats. The American Marten was widespread across the northeastern United States and Canada until hunting and forestry limited this species’ size and geographic range.
American Martens are small predators with long slender bodies, pointed snouts, large eyes, and small cat-like ears. Their feet have curved, retractable claws and large pads (relative to their weight.) These footpads are insulated by long tufts of hair and make it possible to navigate across deep snow.1
Adult males reach a mature length of 20” to 26.5” (their long, bushy tails account for approximately 1/3 of their overall length,) and weight of 1 lb. to 2.9 lbs. Females tend to be smaller (weighing between .6 lb. to 1.9 lbs.) and lighter in color.2 Their long, soft, shiny coats vary in color between individuals (ranging from a light brown or red brown, to a golden brown or buff yellow,) with hair tending to be paler on their heads and undersides, and darker on their legs and tails. They have a cream patch on their chest.
American Martens are solitary animals and are most active at night. They are most often found alone in the wild and only interact during the mating season. Although solitary, they are also curious animals that have been spotted peaking through windows.3 American Martens do not hibernate and remain active all winter. To keep warm during cold months, martens tunnel beneath the snow and huddle amongst tree roots for warmth.4 American Martens are terrestrial mammals that are somewhat arboreal and accomplished swimmers (they are even capable of swimming under water.)
Home ranges of the American Marten vary in size based on gender, location and food supplies. Males’ ranges are approximately 3 square miles while females tend to establish ranges of less than one square mile. Population densities also fluctuate. A healthy habitat can support a density of .7 martens per square mile, while an unhealthy habitat may only support .2 martens per square mile.5
American Martens have complex systems of communication (chemical, vocal, and physical.) Like other members of the mustelid family, American Martens have anal scent glands that secrete a strong odor used to mark territories.6 They also use scent marking to highlight their arboreal trails. Their vocalizations include huffs, screams, and chuckles. Physical interaction is an important component of mating, and the relationship between a mother and her young. American Martens, like other mustelids, are believed to also communicate through body posturing.
The American Marten has a life expectancy of 17 years in captivity. The life expectancy of wild martens is not well documented; however, females in the wild have been known to breed at ages up to 12 years.
American Martens can be found in mature, temperate northern forests at any elevation. They den in ground burrows, crevices or hollowed trees. Within their habitats, they are vulnerable to hawks, owls, fishers, bobcats, and humans.
American Marten populations are distributed throughout northern forests of North America, from Newfoundland and Nova Scotia to Alaska and the northern Rockies. During Colonial times this species was abundant in the northeastern United States, including New York, Maine, Minnesota, and Wisconsin. However, loss of habitat due to forestry practices has limited the marten’s range. Reintroduction programs that were implemented in certain areas have experienced some success in population recovery.
American Martens are opportunistic feeders. Their diets are mainly comprised of small mammals but may also include seasonal fruit and seeds, fish, birds, insects, and carrion. They are terrestrial hunters who do the majority of their hunting on the ground at dawn and dusk. However, they have been known to chase red squirrels (a favorite dietary staple,) and other arboreal species through the trees. Martens attack their prey with a quick bite to the back of the neck.7 In the winter, Martens tunnel through the snow to hunt below the surface.8
The breeding season of the American Marten occurs between June and August. In captivity, females in estrus have been observed to have between 1 and 4 periods of receptiveness during a breeding season, each lasting between 1 and 4 days. These periods are separated by 6 to 17 days. Females in estrus use scent marking to communicate their sexual maturity and readiness. Their long courtships are active and playful, including wrestling and tumbling, and typically occur with more than one partner.
While gestation lasts for a total of 220 to 275 days, the fertilized eggs only develop for the last month of this period. Although eggs are fertilized immediately after copulation, they do not implant in the uterine lining until around February, in a process known as delayed implantation. A litter of 1 to 5 blind, naked young are born in a den of dried vegetation in late March or early April.
There is not a lot of information regarding parental care in the wild. Because the American Marten is a solitary animal, males are not likely to play a large role in the care of young. However, adult males have been observed with mature females and immature young in the wild, likely their own. Females are known to provide care and nourishment for the first few months of her young’s lives, until she leaves them to have another litter.
The young grow quickly. Their eyes are open by 39 days old and they are fully weaned by 42 days old. By 3.5 months old, the young are fully-grown and are left by their mother, who is ready to mate again.
American Martens reach sexual maturity by 15 to 24 months old.
Notes of Interest
The fur of the American Marten is very valuable. However, over hunting and forestry have greatly diminished populations in parts of their range and pelt collection is now controlled in some areas.9
The American Marten is sometimes incorrectly referred to as the Pine Marten, a name derived from a Eurasian species of marten.
The Bobcat, Felis rufus, is the most abundant and widespread native wild cat in North America, named for its short tail that has a docked or “bobbed” appearance. The bobcat is an elusive mammal has been forced to become highly adaptive and can be found in a variety of environments because of habitat loss due to human development.
Bobcats are nearly twice the size of a common housecat, they measure 26” to 41” from head to tail (the tail measuring 4” to 7” in length,) and 17.5” to 23” tall at the shoulder. They are named for their short tails that appear “bobbed” or cut. On average, females are smaller than males. Adult bobcats weigh between 11 lbs. and 30 lbs. Bobcats have long legs and large paws (1) and make tracks that are approximately 2” in diameter (about double the width of housecat tracks) (2). They can be easily identified by the short tufts of hair on their ears (similar to those of the Canada Lynx,) and long, striped ruffs of hair along the sides of the head that create the illusion of sideburns.
Bobcats have an overall brown, buff, or brown-red coat accented by a white underside, black-tipped tail and ears, and dark stripes and spots on the body. In the winter, their coats may grey or dull.3
Bobcats are elusive and nocturnal, making them hard to observe in the wild. They tend to be solitary creatures and only interact during the mating season. Their home ranges are between .5 and over 2.5 square miles, depending on the time of year and location. Male bobcats have larger ranges than females and tend to overlap their ranges with those of several females and sometimes that of another male. Female bobcat ranges do not overlap. Bobcats are territorial and use scent markers to distinguish their ranges and repel intruders. These scent markers may include urine, feces, anal secretions, scratchings, and scrapes (piles of debris collected by a bobcat and marked with their scent.) Bobcats also communicate through sound, although this is typically reserved for the mating season when bobcats produce yowls and hisses. In addition to communication, bobcats also use keen vision, smell, and hearing to navigate their environments and interactions.
Bobcats spend the majority of time on the ground but are agile climbers and can swim.
In the wild, bobcats live an average of 10 to 12 years while in captivity they may live as long as 32 years. (4)
Bobcats have adapted to a diverse range of temperate habitats, including forests, deserts, swamps, brush land, mountains, and suburban areas (5). This diversification has been a necessary result of habitat loss due to development. They prefer habitats with minimal snow accumulation, since (unlike the lynx) bobcat paws are not adapted to navigate across deep snow. (6)
Bobcats build hidden dens in hollow trees, thickets, brush piles, and rocky outcroppings or crevices. While hidden, these dens can be recognized by the strong odors that tend to come from them.
Adults face few threats in their habitats other than humans. Natural enemies are coyotes, wolves and mountain lions. Their kittens are prey to large owls, coyotes, and foxes.
Bobcats can be found across most of North America, from southern parts of Canada through Mexico. Within the United States, bobcat populations tend to be densest in the southeast (7).
Bobcats are opportunistic carnivores and fierce hunters, whose diets consist mainly of rabbits, birds, rodents, and small game (although they are capable of taking down prey much larger then themselves, such as deer.) They have also been known to prey on domestic animals – small dogs as well as outdoor cats. Bobcats are stealthy hunters, using sight and sound to stalk their prey. They wait motionless, then pounce up to 10’, grabbing their prey by the neck and biting through the vertebrae. If a bobcat does not consume its entire kill at once, it will cover the remains with debris or snow and revisit the carcass for future feedings.8
Bobcats are solitary animals and only interact for courtship during the mating season. Breeding occurs once a year (usually in the spring,) during which time females may have multiple partners. After mating, male bobcats play no additional part in reproduction or rearing of the kittens.
Gestation lasts for 60 to 70 days, at which point the female will find a private den and have a little of one to six kittens. The kittens open their eyes at 10 days old and nurse for the first two months. Before the young set out on their own at 9 to 12 months old, their mother brings them meat and teaches them to hunt. Female bobcats reach sexual maturity by one year old, and males by two years.9
Notes of Interest
Bobcats are still trapped for their fur in certain parts of their range.
They are the most widespread and abundant wild cat native to North America. It is estimated that there are as many as one million bobcats in the United States alone.10 With that said, bobcats are quite rare in certain parts of their range, warranting hunting regulations and protection acts.
The Mexican bobcat, Lynx rufus escuinapae, a subspecies of Lynx rufus, is native to central Mexico and listed as endangered by the U.S. Fish and Wildlife Service.11
Bobcats are also referred to as Wildcats, Bay Lynx, Barred Bobcats, Pallid Bobcats, and Red Lynx.12
The honeybee is an incredible and often misunderstood insect. Not only do they impact the majority of the world’s agricultural and wild crops and plants, they also exhibit social structures and communication that far exceed what one might expect from such a diminutive species. What the honeybee lacks in size, they make up for in importance. Unfortunately, the honeybee has experienced a dramatic decline in the last several decades due in part to a number of environmental and human factors. The fate of the honeybee rests in limbo, making it even more important to understand this amazing creature and the invaluable role it plays in the world’s complex ecosystems.
The honeybee, genus is known for its production and storage of honey within perennial, colonial nests, or hives, made of wax note. There are twenty-six recognized subspecies of honeybees, differentiated by morphology, molecular variances, habitat, behavior, and output.
Honeybees vary in size, depending on their roles within the nest. Sterile females, known as workers, are the smallest honeybees, growing to an adult size of 10-15mm in length. Adult males (drones) measure 15-17mm long, and fertile adult females (queens) reach a mature size of 18-20mm long. Honeybees are easily identified by the alternating bands of orange/yellow and black that stretch across their abdomens (useful in warning potential threats.) Their thorax and abdomen are covered in hair, the abdomen tending to have less hair. Pollen baskets, compartments used to store pollen during collection, are located on the dark reddish-brown hind legs. Honeybees have five sets of eyes, three of which are used as light sensors and located at the top of the head, and two with compound lenses. Drones have the largest eyes, believed to aid in locating queens during mating. Honeybees have two sets of wings, which tend to be largest on worker bees. Both workers and queens have stingers that are supplied with venom from glands located in their abdomens1. Bees typically do not sting unless provoked or in defense of their nests or young2. Workers can only sting once in their lifetime since their stingers are barbed and fatally tear away from their body (along with the venom glands) after the sting3.
Honeybees only forage during the day when temperatures and weather conditions are ideal (they will not fly in extreme heat, high winds, or heavy rain and are unable to fly in temperatures below 10°C,) but are active throughout the day within the hive. They are endothermic and are able to warm their bodies and raise the internal temperature of the hive by exercising their flight muscles4. This action is also used to remove the excess moisture from fresh nectar, which needs to be brought from 70% water down to 17% water to produce honey. Honeybees fly at speeds up to 15mph, beating their wings nearly 200 times per second. In a single trip, a honeybee may visit between 50 to 100 pollen sources5.
Honeybees are social insects that live in cooperative hives made of complex cellular structures formed from wax secreted from workers’ bodies. These colonies tend to grow from 10,000 to 15,000 inhabitants in the spring and peak at more than 50,000 inhabitants during the summer, when a queen is in her prime and able to lay up to 3,000 eggs in a single day (assuming she is of good health.)6
Honeybees are divided into three main groups: workers, drones, and queens.
Workers are sterile females and are the bees most often seen outside the hive. Their responsibilities and behaviors within the colony change as they age (known as age polyethism.) New workers clean and prepare cells for food and egg storage. Within a few days, the workers responsibilities change to waste and debris removal, fanning within the hive to regulate air circulation and temperature, processing nectar, and feeding the larvae and queen from glands located within their heads and bodies (this behavior continues into the next behavioral stage.) Within the second week of life, wax glands within the workers’ bodies become active and they begin building and repairing the cells within the hive. These cells are hexagonal and made of wax. Each cell can store one larva, pollen, or honey. The workers then become responsible for guarding and protecting the hive. They survey each bee that enters, driving away strangers and predators. During the fourth week of life, workers; food and wax glands shut down and their sole responsibility becomes foraging7.
The male bees within the colony are called drones. A drone’s sole purpose is to mate with the hive’s queen, although only one in a thousand drones will actually succeed. In a single hive (during the spring and summer) there may be several hundred drones. However, in the winter conditions make it harder for the hive to sustain as many bees so the drones are sometimes expelled.
The third type of bee is the queen. She is integral to a hive’s survival. Not only does the queen lay the eggs (upwards of 3.000 a day during hive build-up in the spring,) she also produces chemicals that regulate the activities of the other bees within the hive. Generally, there is one queen in a hive. When one queen dies, workers will feed one worker “royal jelly” (an elixir that causes the worker to develop into a fertile female – see diet.)8
Each hive has a unique chemical signature that allows bees to recognize hive-mates and be in constant chemical communication with each other (regarding the health of the colony and queen, for example.) Most communication between honeybees is based on chemical signals, specifically taste and scent. Honeybees are able to communicate the location of food supplies by receiving the scent of the food from a returning forager. These returning foragers also communicate the location of food sources through dance. The round dance is used to indicate the presence of food within 300 meters of the hive, while the more complex waggle dance communicates the distance and direction of food further than 300 meters from the hive (using the sun’s position as well as the bees memory to relay the information.) Another instance in which chemicals, or pheromones, communicate information is when a worker stings an enemy. After the stinger and glands are torn from her body, pheromones are released that alert other bees from the hive about the potential threat and help them locate the enemy. Sight is also as important sense for honeybees. They are able to interpret their surrounding environments, recognize threats, spot flowers and food sources, and detect ultraviolet rays (helpful in locating the sun on cloudy days and spotting specific markings on flowers.) A specialized portion of their eyes enables honeybees to see polarized light, useful in navigation. Lastly, vibrations within the hive are important communicative tools. Both workers and queens can sense and create vibrations used to communicate information regarding the behaviors of the queen, the emergence of a new queen, the location of food sources, etc.
Honeybee queens may live up to five years, but on average live between two and three years 9. Workers may experience a lifespan as short as six to eight weeks during their peak production period in the summer. During this period, a worker may fly the equivalent of 1.5 times the earth’s circumference, and as a result, burn out their wings 10. Drones on average live between four to eight weeks.
Honeybees choose habitats that offer ample food sources, such as meadows, gardens, and open wooded areas. They also have success surviving in deserts, grasslands, and wetlands as long as there is water, food and shelter available. Honeybees build their nests within natural cavities.
Within their habitats, honeybees face many predators. Crab spiders, orb-weavers, and several species of wasps are known to attack and wipe out honeybee hives in one blow. Other predators known to attack hives include toads, opossums, bears, honey badgers, birds, skunks, anteaters, chimpanzees, gorillas, rodents, and some ants.
Honeybees are native to Africa, Europe, and western Asia. Starting in the 17th century, Honeybees were introduced by humans into non-native locations, including North and South America, Australia, and eastern Asia. Today, honeybees can be found around the globe (expect for Antarctica and extreme northern climates.)11
Honeybees are herbivorous and workers forage during the day for pollen and nectar for the whole colony. They favor food sources that are close to the nest but may travel as far as 8 miles for food or water. They suck up nectar with their tongues and store it in their, the anterior section of their digestive track. They collect pollen and store it in their pollen baskets, specialized structures located on their hind legs. In moving from one food source to another, honeybees play invaluable roles as pollinators, transferring pollen and seeds from one plant to another, allowing cross-pollination and fertilization to occur. Honeybees, along with other pollinators, affect roughly 30% of the world’s crops and around 90% of the world’s wild plants12. They are opportunistic and have been known to steal from other hives. During the winter months, honeybees (and their larvae) survive on stored pollen and honey and secretions from members of the hive.
After foraging, workers return to the nest and transfer the nectar and pollen to younger workers. These workers are responsible for feeding members of the colony and creating long-term food stores. They secrete specialized enzymes into the honey that allow the water to evaporate and the sugars to concentrate. After eating the pollen and nectar, these young workers are able to secrete royal jelly and worker jelly from glands in their heads. This jelly is fed to the larvae and determines what roles they will later fulfill in the hive (workers or queens.)
Mating occurs during mild weather in the spring or summer. It commences when male honeybees (drones) leave their hives and gather at “drone assembly areas.” Virgin queens, who become sexually mature at five to six days old, emit pheromones as they fly through these areas to attract drones from miles around. Mating occurs in the air and often results in the formation of a, as a cluster of drones surround the queen who are attempting to mate. A virgin queen may mate with up to ten males (from her own hive or other hives,) during each of up to four mating flights she will make during her mating period. These consecutive flights constitute the entirety of a queen’s mating activity for her entire lifetime. Males who succeed in mating die within a few hours or a few days of mating. Other males will stay in the assembly area waiting to mate or until they die. For the rest of her life, a queen bee will lay eggs continuously, typically 1,000 eggs per day and as many as 200,000 in her lifetime. Queen bees in cold climates may cease egg laying for a period of time in the late fall.
Honeybees are holometabolous, meaning they go through four life stages: egg, larva, pupa and adult. Depending on temperature, the eggs hatch in one to six days. Their sex is determined by the queen, who has the ability to lay fertilized or unfertilized eggs. Unfertilized eggs have a haploid set of chromosomes and develop into males or drones, while fertilized eggs have a diploid set of chromosomes and develop into female honeybees (whether they become workers or queens is determined later.) A queen will adjust the type of eggs she is laying depending on the health of her hive and the ratio of males to females within it. Small white grubs emerge from the eggs and stay within their individual wax cells, where adult worker bees feed them. The role a female honeybee plays as an adult is determined by whether she is fed royal jelly as a larva. The female larva that do not receive royal jelly (and will grow into workers) and male larva are fed a combination of pollen, nectar, and honey. The length of the larval stage depends on the type of larva (four to five days for workers, six to seven days for drones, and six days for queens.) At this point, the larva are sealed into their cells, where they molt, spin a cocoon, and transform into a pupa. During the pupa stage, larvae undergo a metamorphosis into an adult honeybee. This process takes twelve days for workers, fourteen to fifteen days for drones, and seven to eight days for queens. Upon completion of this stage, adult honeybees chew their way out of the cells and begin life in their designated roles. Worker bees take a total of three weeks to reach maturity and have a life expectancy of six to eight weeks (although they may live as long as eleven months if they survive during a winter.) Drones take twenty-four days to reach maturity and will only live for four to eight weeks (they do not survive the winter.) Queen bees take sixteen days to reach maturity and live for two to five years.
In addition to individual reproduction, healthy colonies may reproduce too. This event is called swarming and happens one or two times a year, at the start of seasons that produce the most nectar. Swarming commences when workers produce multiple queen larvae. Before the new queens emerge, the original queen flees the hive, taking up to half of its inhabitants with her. This new colony will temporarily nest in a tree while scouts find an adequate location for a permanent hive, where they will build new honeycomb and begin reproduction and food collection. Depending on the number of new queens that emerge in the original hive and the number of inhabitants in the hive, the first few queens that emerge may leave the hive with “afterswarms” and build new hives elsewhere. If the population of the hive is not large enough to produce afterswarms, the emerging queens will fight until only one queen remains, at which point she will begin laying eggs.
Typically the queen is the only bee in the hive that is able to lay eggs (because she secretes pheromones that prevent workers from becoming fertile.) However, in the event that a hive becomes queenless, workers may begin laying unfertilized eggs13.
Notes of Interest
One colony of bees (generally numbering around 30,000 bees) is capable of pollinating one acre of fruit trees.
Nearly two million flowers must be visited in order to produce one pound of honey.
In one flight, a honeybee will visit between fifty and one hundred flowers.
In her lifetime, a worker gathers enough to produce 1/10 of a teaspoon of honey.
The nectar gathered by honeybees is nearly 70% water, while honey is only around 17% water 14.
Honeybees, both wild and domestic, are susceptible to a number of natural health threats, including parasites, pathogenic microbes, at least eighteen different viruses, bacteria, and fungi. One of the most prevalent diseases in domestic hives is Nosema disease, which is cause by Nosema apis, a protozoan. Many of the viruses that cause disease in honeybees are associated with parasitic mites.Within the last twenty years, two specific species of mites have wreaked havoc on the world’s domestic and wild honeybee populations.The first, Acarapis woodi, is a small mite that feeds on bee hemolymph (a fluid in invertebrates that functions like blood) within the tracheas of adult bees.This mite weakens adult bees and may cause whole colonies to fail during cold weather when bees are confined to the hive.This mite was first discovered in European populations, but its exact origins are unknown.The second mite, Varroa destructor, has had a much more severe impact on honeybees. This mite originated in Asian Honeybee colonies but quickly spread to other domesticated honeybee colonies in eastern Asia.This mite is now prevalent on every continent, except Australia.This mite affects a colony in several ways.Young mites feed on larvae and pupae within the hive while adult mites feed on adult honeybees, leaving open wounds.In addition to feeding on honeybees, this mite is also known to carry several viruses that are detrimental to a colonies health.Mite infestations are believed to be at least partially responsible for wiping out almost all of the wild North American colonies, as well as many domestic colonies.The small hive beetle, Aethina turnida, is another threat to honeybees.The beetle larvae consume all the contents of the hive, including the comb, pollen, honey, eggs, and larvae15.
In addition to mite infestations and disease, honeybee populations around the world are succumbing to a number of human factors. Global warming is causing a shift in blooming seasons, resulting in an imbalance between honeybee’s food collecting periods and the availability of food sources. Agricultural pesticides, commonly used by farmers to kill pests, may also harm honeybees. Agricultural, commercial, and residential development has also negatively impacted honeybee populations. Not only are honeybees losing habitats, they are also losing native food sources, which are being removed or replaced by species that are not beneficial to pollinators.
Because of these factors, both environmental and human, bee populations have reached a fifty-year low in countries like the United States, where nearly 1/3 of colonies have vanished. In addition to a sharp decline in honeybee health, within the last decade, farmers and beekeepers have noticed a startling number of healthy adult honeybees abandoning their hives, leaving the queen and adolescents unattended. This phenomenon, referred to as Colony Collapse Syndrome, is believed to partially result from the aforementioned factors but is still not fully understood, making it the topic of much research because of the important role honeybees play in ecosystems and agriculture around the world16.
For more information on honeybees and Colony Collapse Syndrome, check out these sources:
The Ruby-Throated Hummingbird (Archilochus colubris,) is one of m
y favorite backyard sightings, due to its brilliant plumage and spirited behavior. Before you can catch a glance, this acrobatic and energetic bird is usually on its way to the next blossom. This hummingbird has the greatest breeding range of all hummingbirds in North America and occupies much of the eastern United States and Canada during the spring and summer months. By providing the right vegetation and features in your backyard, you may be lucky enough to share your yard with this lovely species.
The Ruby-Throated Hummingbird is named for the metallic ruby-red throat patch found on the throat of the male hummin
gbirds. Both sexes have iridescent green plumage on their backs and heads and white undersides. This species of hummingbird has the lowest number of feathers ever found on any bird1. Females may be distinguished from males by their dull gray throats. The tails also differ between sexes, with forked tails
present on males and white-tipped square tails on females. Young Ruby-Throated Hummingbirds are similar in appearance to adults, except for fewer red feathers on the throats of adolescent males.
Adult hummingbirds reach 3” to 4” in size, averaging 3.5 grams in weight2. Ruby-Throated Hummingbirds have long bills and tongues, used to drink nectar at an average of 13 licks a second. The tongues are grooved to aid in nectar collection and have fringed edges to help collect insects. This acrobatic flyer has short legs relative to their body length, making walking and hopping difficult and inefficient. Possibly the most unique physical attributes of the Ruby-Throated Hummingbird, besides for the red plumage on the males, are the wings. These tiny and delicate appendages are able to beat an average of 53 times per second, creating this bird’s distinctive “humming” noise. During flight the number of beats per second may be 78 times a
second and as high as 200 times a second during a dive (a display used in mating)3. Because of these extreme levels of activity and the tendency to ‘hover’ while eating, Ruby-Throated Hummingbirds have very high metabolic rates. The metabolic rate of these birds at rest is estimated to be 20.6 calories per gram per hour. In addition to their signature hovering, these petite birds are able to fly upside-down and backward.
On average, adult male hummingbirds live to 5 years of age and females live to 9 years in the wild. This species experiences a high mortality rate possibly because of the extreme energy demands of behaviors including breeding displays, migration, and defense of territory, leading to extensive weight loss4.
Ruby-Throated Hummingbird is a solitary species and typically only interact for breeding or territorial purposes. Male hummingbirds are territorial, using vocalizations to ward off intruders. If an intruder enters another male’s territory, the defending male will make a single note, repeating at higher and higher volumes until the intruder retreats. If the vocal warning is not successful, male hummingbirds are known to chase and physically attract other males (using their beaks and feet.)5 In addition to vocalizations, male and female Ruby-Throated Hummingbirds may communicate with and understand olfactory and visual cues. These birds can see the visible light spectrum as well as the blue-violet range. Developed vision along with their sense of smell helps these hummingbirds identify food sources.
Ruby-Throated Hummingbirds are diurnal, most active during the day. When temperatures drop below optimal levels, hummingbirds enter hypothermic torpor in order to conserve energy. Hypothermic torpor is a state similar to hibernation, allowing a hummingbird to conserve energy through a lowered body temperature and slowed body functions6.
Populations of Ruby-Throated Hummingbirds are wide spread and numerous, with an estimated 7.3 million birds worldwide. This species has never experienced any serious threats and is protected under the Migratory Bird Treaty between the U.S. and Canada. As with all hummingbird species, the Ruby-Throated Hummingbird is part of Appendix II of the Convention on International Trade in Endangered Species7.
Ruby-Throated Hummingbirds fulfill an important role in their habitats, pollinating flowers, shrubs and vines. This symbiotic relationship is so strong that some species of plants have adapted to cater specifically to these small birds. Ruby-Throated Hummingbirds are migratory, inhabiting northern habitats during their summer breeding season and tropical habitats after migrating south for the winter. Preferred habitats include deciduous and pine forests, mixed woodlands, orchards, flowering gardens, parks, overgrown pastures, and citrus groves. The Ruby-Throated Hummingbird selects habitats that are close in proximity to water sources such as marshes or streams, to ensure abundant insect supplies8.
Males establish territories that offer food supplies, protection and mating opportunities. Some males have been known to establish a breeding territory distinct from their primary territory when food sources in the primary territory were not sufficient to support mating activities. These separate areas may be as far as two miles apart. Males are defensive of their territories and typically locate their territory at least 50’ away from a territory of another male Ruby-Throated Hummingbird. Territories of Ruby-Throated Hummingbirds may overlap with those of other hummingbird species. In these instances, the male Ruby-Throated Hummingbird will become submissive9.
Within their habitats, Ruby-Throated Hummingbirds are vulnerable to birds-of-prey (including blue jays which feed on nestlings) and, most often, house cats.
Ruby-Throated Hummingbirds are a migratory species. Between February and May these petite birds fly north to their breeding grounds located across the eastern United States and Canada, east of the 100th meridian. Between July and October Ruby-Throated Hummingbirds embark on a southern migration to their winter grounds that extend from southern Florida south to Panama and the West Indies. This species primarily winters in Central America. Ruby-Throated Hummingbirds are capable of a nonstop, 500-mile flight across the Gulf of Mexico and may go so far as to double their body weight in preparation. The migration of this species coordinates with the blooming schedules of flowers.
Ruby-Throated Hummingbirds are omnivorous, feeding on flowers and nectar as well as insects. Adult hummingbirds require an immense amount of calories to support their behaviors and must consume approximately twice their body weight a day. They are most often spotted hovering over flowers as they lick the nectar, consuming approximately half their body weight in sugar a day, spread between five to eight feedings10. Preference has been shown for red flowers, but hummingbirds consume a variety of other flowers and nectar from wildflowers and flowers from shrubs and vines, as well as tree sap (collected from wells excavated by tree-boring bird species.) Insects are collected from sap wells and vegetation and include mosquitoes, small bees, gnats, small flies, aphids, spiders, caterpillars and insect eggs11.
If you are looking to attract hummingbirds to your garden, here is a variety of plantings you may consider:
Begonia, Century Plant, Butterfly Weed, Columbine, Delphinium, Fox Glove, Dahlia, Geranium, Impatients, Lilly, Petunia, Phlox, Snapdragons, Verbena, Sweet William
Vines, Trees, Shrubs:
Honeysuckle, Trumpet Vine, Morning Glory, Butterfly Bush, Rose of Sharon, rosemary, Tulip Poplar
Hanging a hummingbird feeder is also a great way to attract these beautiful birds. Fill your feeder with a concentrated sugar solution (roughly 4 parts sugar to 1 part water.) Boil the mixture until the sugar is fully dissolved. Remember to clean your feeder often, especially during extreme heat. The sugar solution should be changed every few days, especially during high temperatures because heat can cause this solution to spoil.
*Do not use artificial sweetener or honey in your feeder. Honey can ferment and cause hummingbirds to become sick and sweeteners contain no nutritional value13.
Ruby-Throated Hummingbirds breed while in their northern habitats between March and July, the height of breeding occurring in mid-May. This species inhabits a larger breeding range than all other hummingbird species in North America and is the only species of hummingbird that breeds east of the Mississippi14.
Both male and female Ruby-Throated Hummingbirds take several breeding partners during a given season, although no long-term breeding pairs are established. After copulation pairs separate and females assume all parental duties.
Male Ruby-Throated Hummingbirds return to breeding areas in the spring to establish their territories prior to females’ arrivals. Upon entering a male’s territory, a female will be courted with an acrobatic display: a showy display of red throat plumage and diving displays with males flying in loops above the females. If a female shows interest by perching, the male will proceed by flying in fast horizontal arcs just feet in front of the female. Females may give their final consent by emitting a “mew” and displaying a posture of cocked tail feathers and lowered wings15.
Females are solely responsible for selecting the site for and building a nest. Nests are typically attached to a down-sloping branch by pine resin, below a shelter of leaves, 5’ to 20’ off the ground or a stream. Common trees to find hummingbird nests in are oak, maple, poplar, birch, beech, spruce and pine. Nests are constructed of thistle, ferns, young leaves, moss, dandelion and milkweed down, spider and caterpillar webs, and bud scales and decorated on the exterior with lichen (possibly to provide camouflage.)
Females lay, on average, 1 to 3 small white eggs. After two weeks of incubation, the young birds are born and will be fed by their mothers in the nest for approximately 3 weeks. The chicks leave the nest about 20 days after hatching and reach sexual maturity at 1 year of age. In a single breeding season a female may have several broods.
Notes of Interest:
While hummingbirds don’t require a source of water for drinking, providing a water feature in your garden may help attract these beautiful birds. Including a fountain, pond, birdbath, waterfall or mister in your garden may increase insect populations and make your space more attractive.
Ruby-Throated Hummingbirds were a prized specimen in the nineteenth century due to their beautiful plumage. Although these birds were commonly hunted and a coveted prize, this species never became threatened and numbers stayed strong and stable16.