The northwestern crow is an all-black passerine bird of the crow genus native to the northwest of North America. It is similar to the more western forms of the widespread American crow, but it averages smaller with proportionately smaller feet and a more slender bill; this taxon is reliably identified by range only. This species was described by Spencer Fullerton Baird in 1858; the American Ornithologists' Union considers it related to the American crow and it may be conspecific. Hybrids with American crows have been reported, but not confirmed; this species' plumage is identical to that of the American crow. Individuals may be distinguished by in-hand criteria such as smaller wing chord and tail length, shorter tarsus, smaller bill. Identification percentages increase. Like the American crow, the sexes look the same. Older birds in breeding condition may be reliably sexed by in-hand criteria such as cloacal protuberance or by brood patch. Younger birds may not attain breeding condition; this species occurs in coastal regions and offshore islands of southern Alaska, south through British Columbia to Washington.
Beaches and shorelines are the principal forage areas. It can be seen in and around urban areas. Similar to that of the fish crow, it has been seen to fly into the air with mussels and drop them onto hard surfaces to break them open. It regularly eats insects, other invertebrates, various fruits, it raids other birds' nests to eat hatchlings. An incomplete list includes cats, raccoons and ravens; the crows gather in large groups to mob these predators. Solitary, but sometimes built in association with a few other individuals in small, loose colonies in trees or sometimes large bushes, it will nest on cliffs in a recess or on the ground in a remote area if overhung by a rock for shelter. It is a typical crow nest with 4-5 eggs laid; the voice is varied, many types of call are made, but the most common are described as a high pitched "caw" and the sound of a cork coming out of a bottle. A "wok-wok-wok" is given by a bird in flight if straggling behind the group, various clicks and mechanical sounding rattles are heard.
Image links Walking on the ground Perching on a rail Urban bird walking on pavement Skull of Northwestern Crow Northwestern Crow photo gallerySound links Northwestern Crow call Video links Corvus caurinus videos on the Internet Bird Collection
Northeastern United States
The Northeastern United States referred to as the Northeast, is a geographical region of the United States bordered to the north by Canada, to the east by the Atlantic Ocean, to the south by the Southern United States, to the west by the Midwestern United States. The Northeast is one of the four regions defined by the United States Census Bureau for the collection and analysis of statistics; the Census Bureau-defined region has a total area of 181,324 sq mi with 162,257 sq mi of that being land mass. Although it lacks a unified cultural identity, the Northeastern region is the nation's most economically developed, densely populated, culturally diverse region. Of the nation's four census regions, the Northeast is the second most urban, with 85 percent of its population residing in urban areas, led by the West with 90 percent. Geographically there has always been some debate as to where the Northeastern United States begins and ends; the vast area from central Virginia to northern Maine, from western Pennsylvania to the Atlantic Ocean, have all been loosely grouped into the Northeast at one time or another.
Much of the debate has been what the cultural and urban aspects of the Northeast are, where they begin or end as one reaches the borders of the region. Using the Census Bureaus definition of the northeast, the region includes nine states: they are Maine, New York, New Jersey, Massachusetts, Rhode Island, New Hampshire, Pennsylvania; the region is subdivided into New England and the Mid-Atlantic states. This definition has been unchanged since 1880 and is used as a standard for data tabulation. However, the Census Bureau has acknowledged the obvious limitations of this definition and the potential merits of a proposal created after the 1950 census that would include changing regional boundaries to include Delaware and the District of Columbia, with the Mid-Atlantic states, but decided that "the new system did not win enough overall acceptance among data users to warrant adoption as an official new set of general-purpose State groupings; the previous development of many series of statistics and issued over long periods of time on the basis of the existing State groupings, favored the retention of the summary units of the current regions and divisions."
The Census Bureau confirmed in 1994 that it would continue to "review the components of the regions and divisions to ensure that they continue to represent the most useful combinations of States and State equivalents."Many organizations and reference works follow the Census Bureau's definition for the region. The Association of American Geographers divides the Northeast into two divisions: "New England", which consists of Maine, New Hampshire, Rhode Island, Connecticut; the Geological Society of America defines the Northeast as these same states but with the addition of Maryland and the District of Columbia. The narrowest definitions include only the states of New England. Other more restrictive definitions include New England and New York as part of the Northeast United States, but exclude Pennsylvania and New Jersey. States beyond the Census Bureau definition are included in Northeast Region by various other entities: Various organizations include: Delaware and District of Columbia; the US EPA and NOAA include in their Northeast Region: Delaware and West Virginia.
The National Fish and Wildlife Service includes in their Northeast Region: Delaware, District of Columbia, West Virginia, Virginia. The National Park Service includes in their Northeast Region: Delaware, West Virginia, Virginia. Anthropologists recognize the "Northeastern Woodlands" as one of the cultural regions that existed in the Western Hemisphere at the time of European colonists in the 15th and centuries. Most did not settle in North America until the 17th century; the cultural area, known as the "Northeastern Woodlands", in addition to covering the entire Northeast U. S. covered much of what is now Canada and others regions of what is now the eastern United States. Among the many tribes that inhabited this area were those that made up the Iroquois nations and the numerous Algonquian peoples. In the United States of the 21st century, 18 federally recognized tribes reside in the Northeast. For the most part, the people of the Northeastern Woodlands, on whose lands European fishermen began camping to dry their codfish in the early 1600s, lived in villages after being influenced by the agricultural traditions of the Ohio and Mississippi valley societies.
All of the states making up the Northeastern region were among the original Thirteen Colonies, though Maine and Delaware were part of other colonies before the United States became independent in the American Revolution. The two cultural and geographic regions that form parts of the Northeastern region have distinct histories; the first Europeans to settle New England were Pilgrims from England, who landed in present-day Massachusetts in 1620. The Pilgrims arrived by the Mayflower ship and founded Plymouth Colony so they could practice religion freely. Ten years a larger group of Puritans settled north of Plymouth Colony in Boston to form Massachusetts Bay Colony. In 1636, colonists established Providence Plantations. Providence was founded by Roger Williams, banished
Corvus is a distributed genus of medium-sized to large birds in the family Corvidae. The genus includes species known as crows, ravens and jackdaws. Ranging in size from the small pigeon-sized jackdaws to the common raven of the Holarctic region and thick-billed raven of the highlands of Ethiopia, the 45 or so members of this genus occur on all temperate continents except South America, several islands; the crow genus makes up a third of the species in the family Corvidae. The members appear to have evolved in Asia from the corvid stock; the collective name for a group of crows is a "flock" or a "murder". The genus name is Latin for "raven". Recent research has found some crow species capable of not only tool use, but tool construction. Crows are now considered to be among the world's most intelligent animals with an encephalization quotient equal to that of many non-human primates. Corvus species are all black with little white or grey plumage, they are stout with strong legs. Sexual dimorphism is limited.
The members of the genus Corvus are believed to have evolved in central Asia and radiated out into North America, Africa and Australia. The latest evidence regarding the evolution indicates descent within the Australasian family Corvidae. However, the branch that would produce the modern groups such as jays and large, predominantly black Corvus species had left Australasia and were concentrated in Asia by the time the Corvus species evolved. Corvus produced five species with one recognized subspecies; the genus was described by Linnaeus in his 18th-century work Systema Naturae. The name is derived from the Latin corvus meaning "raven"; the type species is the common raven. The genus was broader, as the magpie was designated C. pica before being moved into a genus of its own. At least 42 extant species are now considered to be in this genus, at least 14 extinct species have been described; the fossil record of crows is rather dense in Europe, but the relationships among most prehistoric species are not clear.
Corvids are found in major cities across the world, a major increase in the number of crows in urban settings has occurred since the 1900s. Historical records suggest that the population of American crows found in North America has been growing since the introduction of European colonization, spread east to west with the opening of the frontier. Crows were uncommon in the Pacific Northwest in the 1900s. Populations in the west increased from the late 1800s to mid 1900s. Crows and ravens spread along with agriculture and urbanization into the western part of North America. Crows gather in large communal roosts numbering between 200 and tens of thousands of individuals during nonbreeding months in the winter; these gatherings tend to happen near large food sources such as garbage dumps and shopping centers. Countless incidents are recorded of corvids at play. Many behaviourists see play as an essential quality in intelligent animals. Crows and the other members of the genus make a wide variety of vocalizations.
Crows have been observed to respond to calls of other species. Crows' vocalizations are complex and poorly understood; some of the many vocalizations that crows make are a "koww" echoed back and forth between birds, a series of "kowws" in discrete units, a long caw followed by a series of short caws, an echo-like "eh-aw" sound, more. These vocalizations vary by species, within each species they vary regionally. In many species, the pattern and number of the numerous vocalizations have been observed to change in response to events in the surroundings; as a group, crows show remarkable examples of intelligence. Natural history books from the 18th century recount an often-repeated, but unproven anecdote of "counting crows" — a crow whose ability to count to five is established through a logic trap set by a farmer. Crows and ravens score highly on intelligence tests. Certain species top the avian IQ scale. Wild hooded crows in Israel have learned to use bread crumbs for bait-fishing. Crows air - "chicken" to establish pecking order.
They have been found to engage in activities such as sports, tool use, the ability to hide and store food across seasons, episodic-like memory, the ability to use individual experience in predicting the behavior of environmental conspecifics. One species, the New Caledonian crow, has been intensively studied because of its ability to manufacture and use tools in the day-to-day search for food. On 5 October 2007, researchers from the University of Oxford presented data acquired by mounting tiny video cameras on the tails of New Caledonian crows, they pluck and bend twigs and grass stems to procure a variety of foodstuffs. Crows in Queensland have learned how to eat the toxic cane toad by flipping the cane toad on its back and violently stabbing the throat where the skin is thinner, allowing the crow to access the nontoxic innards. The
The common raven known as the northern raven, is a large all-black passerine bird. Found across the Northern Hemisphere, it is the most distributed of all corvids. There are at least eight subspecies with little variation in appearance, although recent research has demonstrated significant genetic differences among populations from various regions, it is one of the two largest corvids, alongside the thick-billed raven, is the heaviest passerine bird. Common ravens can live up to 21 years in the wild, a lifespan surpassed among passerines by only a few Australasian species such as the satin bowerbird and the lyrebirds. Young birds may travel in flocks but mate for life, with each mated pair defending a territory. Common ravens have coexisted with humans for thousands of years and in some areas have been so numerous that people have regarded them as pests. Part of their success as a species is due to their omnivorous diet; some notable feats of problem-solving provide evidence that the common raven is unusually intelligent.
Over the centuries, it has been the subject of mythology, folklore and literature. In many cultures, including the indigenous cultures of Scandinavia, ancient Ireland and Wales, the northwest coast of North America, Siberia and northeast Asia, the common raven has been revered as a spiritual figure or godlike creature; the common raven was one of the many species described by Linnaeus in his 18th century work, Systema Naturae, it still bears its original name of Corvus corax. It is the type species of the genus Corvus, derived from the Latin word for "raven"; the specific epithet, corax/κοραξ, is the Ancient Greek word for "raven" or "crow". The modern English word raven has cognates in all other Germanic languages, including Old Norse hrafn and Old High German raban, all which descend from Proto-Germanic *khrabanas. An old Scottish word corby or corbie, akin to the French corbeau, has been used for both this bird and the carrion crow. Obsolete collective nouns for a group of ravens include "unkindness" and "conspiracy".
In practice, most English-speakers use the more generic "flock". The closest relatives of the common raven are the brown-necked raven, the pied crow of Africa, the Chihuahuan raven of the North American southwest. While some authorities have recognized as many as 11 subspecies, others recognize only eight: The common raven evolved in the Old World and crossed the Bering land bridge into North America. Recent genetic studies, which examined the DNA of common ravens from across the world, have determined that the birds fall into at least two clades: a California clade, found only in the southwestern United States, a Holarctic clade, found across the rest of the Northern Hemisphere. Birds from both clades look alike, but the groups are genetically distinct and began to diverge about two million years ago; the findings indicate that based on mitochondrial DNA, common ravens from the rest of the United States are more related to those in Europe and Asia than to those in the California clade, that common ravens in the California clade are more related to the Chihuahuan raven than to those in the Holarctic clade.
Ravens in the Holarctic clade are more related to the pied crow than they are to the California clade. Thus, the common raven species as traditionally delimited is considered to be paraphyletic. One explanation for these genetic findings is that common ravens settled in California at least two million years ago and became separated from their relatives in Europe and Asia during an ice age. One million years ago, a group from the California clade evolved into a new species, the Chihuahuan raven. Other members of the Holarctic clade arrived in a separate migration from Asia at the same time as humans. A 2011 study suggested that there are no restrictions on gene flow between the Californian and Holarctic common raven groups, that the lineages can remerge reversing a potential speciation. A recent study of raven mitochondrial DNA showed that the isolated population from the Canary Islands is distinct from other populations; the study did not include any individuals from the North African population, its position is therefore unclear, though its morphology is close to the population of the Canaries.
A mature common raven ranges between 67 cm long, with a wingspan of 115 to 150 cm. Recorded weights range from 0.69 to 2 kg, thus making the common raven one of the heaviest passerines. Birds from colder regions such as the Himalayas and Greenland are larger with larger bills, while those from warmer regions are smaller with proportionally smaller bills. Representative of the size variation in the species, ravens from California weighed an average of 784 g, those from Alaska weighed an average of 1,135 g and those from Nova Scotia weighed an average of 1,230 g; the bill is large and curved, with a culmen length of 5.7 to 8.5 cm one of the largest bills amongst passerines. It has a longish graduated tail, at 20 to 26.3 cm, black iridescent plumage, a dark brown iris. Th
An ice age is a long period of reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth is in the Quaternary glaciation, known in popular terminology as the Ice Age. Individual pulses of cold climate are termed "glacial periods", intermittent warm periods are called "interglacials", with both climatic pulses part of the Quaternary or other periods in Earth's history. In the terminology of glaciology, ice age implies the presence of extensive ice sheets in both northern and southern hemispheres. By this definition, we are in an interglacial period—the Holocene; the amount of heat trapping gases emitted into Earth's Oceans and atmosphere will prevent the next ice age, which otherwise would begin in around 50,000 years, more glacial cycles. In 1742, Pierre Martel, an engineer and geographer living in Geneva, visited the valley of Chamonix in the Alps of Savoy. Two years he published an account of his journey.
He reported that the inhabitants of that valley attributed the dispersal of erratic boulders to the glaciers, saying that they had once extended much farther. Similar explanations were reported from other regions of the Alps. In 1815 the carpenter and chamois hunter Jean-Pierre Perraudin explained erratic boulders in the Val de Bagnes in the Swiss canton of Valais as being due to glaciers extending further. An unknown woodcutter from Meiringen in the Bernese Oberland advocated a similar idea in a discussion with the Swiss-German geologist Jean de Charpentier in 1834. Comparable explanations are known from the Val de Ferret in the Valais and the Seeland in western Switzerland and in Goethe's scientific work; such explanations could be found in other parts of the world. When the Bavarian naturalist Ernst von Bibra visited the Chilean Andes in 1849–1850, the natives attributed fossil moraines to the former action of glaciers. Meanwhile, European scholars had begun to wonder. From the middle of the 18th century, some discussed ice as a means of transport.
The Swedish mining expert Daniel Tilas was, in 1742, the first person to suggest drifting sea ice in order to explain the presence of erratic boulders in the Scandinavian and Baltic regions. In 1795, the Scottish philosopher and gentleman naturalist, James Hutton, explained erratic boulders in the Alps by the action of glaciers. Two decades in 1818, the Swedish botanist Göran Wahlenberg published his theory of a glaciation of the Scandinavian peninsula, he regarded glaciation as a regional phenomenon. Only a few years the Danish-Norwegian geologist Jens Esmark argued a sequence of worldwide ice ages. In a paper published in 1824, Esmark proposed changes in climate as the cause of those glaciations, he attempted to show. During the following years, Esmark's ideas were discussed and taken over in parts by Swedish and German scientists. At the University of Edinburgh Robert Jameson seemed to be open to Esmark's ideas, as reviewed by Norwegian professor of glaciology Bjørn G. Andersen. Jameson's remarks about ancient glaciers in Scotland were most prompted by Esmark.
In Germany, Albrecht Reinhard Bernhardi, a geologist and professor of forestry at an academy in Dreissigacker, since incorporated in the southern Thuringian city of Meiningen, adopted Esmark's theory. In a paper published in 1832, Bernhardi speculated about former polar ice caps reaching as far as the temperate zones of the globe. In 1829, independently of these debates, the Swiss civil engineer Ignaz Venetz explained the dispersal of erratic boulders in the Alps, the nearby Jura Mountains, the North German Plain as being due to huge glaciers; when he read his paper before the Schweizerische Naturforschende Gesellschaft, most scientists remained sceptical. Venetz convinced his friend Jean de Charpentier. De Charpentier transformed Venetz's idea into a theory with a glaciation limited to the Alps, his thoughts resembled Wahlenberg's theory. In fact, both men shared the same volcanistic, or in de Charpentier's case rather plutonistic assumptions, about the Earth's history. In 1834, de Charpentier presented his paper before the Schweizerische Naturforschende Gesellschaft.
In the meantime, the German botanist Karl Friedrich Schimper was studying mosses which were growing on erratic boulders in the alpine upland of Bavaria. He began to wonder. During the summer of 1835 he made some excursions to the Bavarian Alps. Schimper came to the conclusion that ice must have been the means of transport for the boulders in the alpine upland. In the winter of 1835 to 1836 he held. Schimper assumed that there must have been global times of obliteration with a cold climate and frozen water. Schimper spent the summer months of 1836 at Devens, near Bex, in the Swiss Alps with his former university friend Louis Agassiz and Jean de Charpentier. Schimper, de Charpentier and Venetz convinced Agassiz that there had been a time of glaciation. During the winter of 1836/37, Agassiz and Schimper developed the theory of a sequence of glaciations, they drew upon the preceding works of Venetz, de Charpentier and on their own fieldwork. Agassiz appears to have been familiar with Bernhardi's paper at that time.
At the beginning of 1837, Schimper coined the term "ice age" for the period of the glaciers. In July 1837 Ag
Florida is the southernmost contiguous state in the United States. The state is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Atlantic Ocean, to the south by the Straits of Florida. Florida is the 22nd-most extensive, the 3rd-most populous, the 8th-most densely populated of the U. S. states. Jacksonville is the most populous municipality in the state and the largest city by area in the contiguous United States; the Miami metropolitan area is Florida's most populous urban area. Tallahassee is the state's capital. Florida's $1.0 trillion economy is the fourth largest in the United States. If it were a country, Florida would be the 16th largest economy in the world, the 58th most populous as of 2018. In 2017, Florida's per capita personal income was ranking 26th in the nation; the unemployment rate in September 2018 was 3.5% and ranked as the 18th in the United States. Florida exports nearly $55 billion in goods made in the 8th highest among all states.
The Miami Metropolitan Area is by far the largest urban economy in Florida and the 12th largest in the United States with a GDP of $344.9 billion as of 2017. This is more than twice the number of the next metro area, the Tampa Bay Area, which has a GDP of $145.3 billion. Florida is home to 51 of the world's billionaires with most of them residing in South Florida; the first European contact was made in 1513 by Spanish explorer Juan Ponce de León, who called it la Florida upon landing there in the Easter season, known in Spanish as Pascua Florida. Florida was a challenge for the European colonial powers before it gained statehood in the United States in 1845, it was a principal location of the Seminole Wars against the Native Americans, racial segregation after the American Civil War. Today, Florida is distinctive for its large Cuban expatriate community and high population growth, as well as for its increasing environmental issues; the state's economy relies on tourism and transportation, which developed in the late 19th century.
Florida is renowned for amusement parks, orange crops, winter vegetables, the Kennedy Space Center, as a popular destination for retirees. Florida is the flattest state in the United States. Lake Okeechobee is the largest freshwater lake in the U. S. state of Florida. Florida's close proximity to the ocean influences many aspects of daily life. Florida is a reflection of multiple inheritance. Florida has attracted many writers such as Marjorie Kinnan Rawlings, Ernest Hemingway and Tennessee Williams, continues to attract celebrities and athletes, it is internationally known for golf, auto racing, water sports. Several beaches in Florida have emerald-colored coastal waters. About two-thirds of Florida occupies a peninsula between the Gulf of the Atlantic Ocean. Florida has the longest coastline in the contiguous United States 1,350 miles, not including the contribution of the many barrier islands. Florida has a total of 4,510 islands; this is the second-highest number of islands of any state of the United States.
It is the only state that borders both the Gulf of the Atlantic Ocean. Much of the state is characterized by sedimentary soil. Florida has the lowest high point of any U. S. state. The climate varies from subtropical in the north to tropical in the south; the American alligator, American crocodile, American flamingo, Roseate spoonbill, Florida panther, bottlenose dolphin, manatee can be found in Everglades National Park in the southern part of the state. Along with Hawaii, Florida is one of only two states that has a tropical climate, is the only continental state with either a tropical climate or a coral reef; the Florida Reef is the only living coral barrier reef in the continental United States, the third-largest coral barrier reef system in the world. By the 16th century, the earliest time for which there is a historical record, major Native American groups included the Apalachee of the Florida Panhandle, the Timucua of northern and central Florida, the Ais of the central Atlantic coast, the Tocobaga of the Tampa Bay area, the Calusa of southwest Florida and the Tequesta of the southeastern coast.
Florida was the first region of the continental United States to be visited and settled by Europeans. The earliest known European explorers came with the Spanish conquistador Juan Ponce de León. Ponce de León spotted and landed on the peninsula on April 2, 1513, he named the region Florida. The story that he was searching for the Fountain of Youth is mythical and only appeared long after his death. In May 1539, Conquistador Hernando de Soto skirted the coast of Florida, searching for a deep harbor to land, he described seeing a thick wall of red mangroves spread mile after mile, some reaching as high as 70 feet, with intertwined and elevated roots making landing difficult. The Spanish introduced Christianity, horses, the Castilian language, more to Florida. Spain established several settlements with varying degrees of success. In 1559, Don Tristán de Luna y Arellano established a settlement at present-day Pensacola, making it the first attempted settlement in Florida, but it was abandoned by 1561.
In 1565, the settlement of St. Augustine was established under the leadership of admiral and
Christian Ludwig Brehm
Christian Ludwig Brehm was a German pastor and ornithologist. He was the father of the zoologist Alfred Brehm. Brehm was born near Gotha, studied at the University of Jena. In 1813 he became the minister at Renthendorf, a village sixty miles south of Leipzig, where he remained until his death, his extensive writings included Beiträge zur Vogelkunde, which described 104 species of German birds in minute detail, Handbuch der Naturgeschichte aller Vögel Deutschlands. Brehm accumulated a collection of 15,000 bird skins, he offered these to the Berlin Zoological Museum. After his death they remained in the attic of his house, where Otto Kleinschmidt discovered them some years later. Kleinschmidt persuaded Lord Rothschild to buy them, the collection arrived at his Natural History Museum at Tring. C. L. Brehm: Beiträge zur Vogelkunde 3 Bde, ab Bd. 3 in collaboration with W. Schilling. - Neustadt a. Orla 1820-1822. C. L. Brehm: Lehrbuch der Naturgeschichte aller europäischen Vögel, 2 Bde. - Jena 1823-1824 C. L. Brehm: Ornis oder das Neueste und Wichtigste der Vogelkunde - Jena 1824-1827, first ornithologic journal.
C. L. Brehm: Handbuch der Naturgeschichte aller Vögel Deutschlands - Ilmenau 1831. C. L. Brehm: Handbuch für den Liebhaber der Stuben-, Haus- und aller der Zähmung werthen Vögel - Ilmenau 1832. C. L. Brehm: Der Vogelfang - Leipzig 1836. C. L. Brehm: Der vollständige Vogelfang - Weimar 1855. C. L. Brehm: Die Kunst, Vögel als Bälge zu bereiten - Weimar 1842. C. L. Brehm: Die Wartung, Pflege und Fortpflanzung der Canarienvögel - Weimar 1855, 2. Aufl. Weimar 1865, 3. Aufl. Weimar 1872, 4. Auflage Weimar 1883, 5. Aufl. Weimar 1893. C. L. Brehm: Die Naturgeschichte und Zucht der Tauben - Weimar 1857. E. Baldamus, C. L. Brehm, John Wilhelm von Müller & J. F. Naumann: Verzeichnis der Vögel Europa's. Als Tausch-Catalog eingerichtet. - Stuttgart 1852 C. L. Brehm: Monographie der Papageien oder vollständige Naturgeschichte aller bis jetzt bekannten Papageien mit getreuen und ausgemalten Abbildungen, im Vereine mit anderen Naturforscher herausgegeben von C. L. Brehm. - Jena & Paris 1842-1855 Academy of Sciences Leopoldina The Bird Collectors, by Barbara and Richard Mearns ISBN 0-12-487440-1 Website advertising the Brehm Memorial Center in Renthendorf, a museum inside the former home of Christian Ludwig Brehm, his family and his son Alfred Brehm