the genus sayornis is a small group of medium-sized insect-eating birds , known as phoebes , in the tyrant flycatcher family tyrannidae .

the genus name sayornis is constructed from the specific part of charles lucien bonaparte 's name for say 's phoebe , muscicapa saya , and ancient greek ornis , " bird " .

the english phoebe is a name for the roman moon-goddess diana .

phoebe ( bird )

of the three phoebe species , the eastern phoebe’s call most closely resembles its name .
some bird guides eschew words for more literal translations of a bird ' s song , but doing so ignores the point of mnemonic devices : aiding memory .
the eastern phoebe was the first bird to be banded in north america . in 1804 , john james audubon used a silver thread attached to its leg to note when the bird would return each year .
@ parakeets : if the bird is capable of flight let it go . otherwise , small portions of ground beef ( you might have to force it into the bird’s mouth until it learns to eat it ) until you can get the bird to a wildlife rehabilitater .
in 1804 , the eastern phoebe became the first banded bird in north america . john james audubon attached silvered thread to an eastern phoebe ' s leg to track its return in successive years .
another
first
; the eastern phoebe was the first north american bird to be banded for study . john james audubon banded an individual with a silvered thread in 1804 , so he could document this bird ' s return the following spring .
question : this seemingly unremarkable mystery bird is a remarkable
first
in north america . can you tell me about that
first
? this mystery bird will be challenging for you to identify from this image , but i think most of you can identify this bird ' s taxonomic family at least . can you identify this bird and tell me how to distinguish it from its family members ?
eastern phoebe , sayornis phoebe ( protonym , muscicapa [ ] phoebe ) , latham , 1790 , also known as the phoebe , as the bridge pewee or as the water pewee , photographed at white hall , virginia ( usa ) .
tell congress and the department of the interior to uphold the country ' s most important bird protection law .
response : this is an eastern phoebe , sayornis phoebe , the most common tyrant flycatcher ( family ; tyrannidae ) species that you ' ll see in the eastern united states . this migratory bird , which winters in central america , also pops up in western europe from time to time , giving the local birders a thrill .
white breasted nuthatch , black phoebe and titmouse interacting at the birdbath at las pilitas nursery .
say’s phoebe ( sayornis saya ) is the most colorful of the phoebes , gray above but a smart buffy orange below . it’s also the hardiest , breeding as far north as the alaskan arctic , much further north , in fact , than any other flycatcher . looking at its range map , this phoebe seems to have split the u . s . with its eastern cousin . say’s phoebe is named for the noted american naturalist , thomas say , who provided the first official descriptions of this bird and a number of other western species . one might find it ironic that say , considered the founder of descriptive entomology in the united states , has a bird named for him , but the fact that say’s phoebe is a flycatcher seems rather poetic .
mike is a leading authority in the field of standardized test preparation , but he ' s also a traveler who fully expects to see every bird in the world . besides founding 10 , 000 birds , mike has also created a number of other entertaining but now extirpated nature blog resources , particularly the nature blog network and i and the bird .
the black phoebe ( sayornis nigricans ) won’t be mistaken for any other bird ; nothing else that size shows such dark plumage with a white belly to contrast . this phoebe is a fixture in the american southwest and central america and can be spotted all the way down to argentina . black phoebes eat bugs with the same gusto as any other flycatcher , but will also go after tiny fish .
the black phoebe hawks insects , usually over water or near water . it will occasionally eat small fish .
the black phoebe does not migrate . however , they will move around a little in spring and fall .
lutmerding , j . a . and a . s . love . longevity records of north american birds . version 2015 . 2 . patuxent wildlife research center , bird banding laboratory 2015 .
there are many ways to contribute—we need species information , photographs , audio , video , translations , maps , distribution data , and bird sightings . there ' s a role for everyone !
when the word “phoebe” comes up , most people automatically think of things like the outermost of saturn’s known satellites , the greek titan - goddess of the moon , or the most fascinating and complex character from that happily departed sitcom , friends . anyone who has gone bird watching in north america , however , knows another kind of phoebe , a bold little genus that turns up with remarkable frequency from the arctic circle to the equator .
the eastern phoebe is a rather dull phoebe found in the east and across central canada . it frequently nests under eaves , bridges , or other overhangs on human - made structures . the eastern phoebe is most easily separated from other dull flycatchers by its characteristic habit of dipping its tail in a circular motion . monotypic . length 4 . 5
.
i haven’t heard that before , rick , but can absolutely see why . vermilion phoebe isn’t quite as catchy though !
thanks , corey . as a matter of fact , i have seen a bird flying under the deck today , which is where the nest is , so mom & dad may be thinking about that second brood . couldn’t tell if it was a phoebe , but i’ll be on the lookout . we need them for bug control !
a few other exceptions to this color scheme are the frosty plumage of the scissor - tailed flycatcher highlighted by salmon pink underwings , the orangish coloration of the say’s phoebe , and the black and white plumages of the eastern kingbird and black phoebe .
there’s a good case to be made that vermilion flycatcher is also a “phoebe , ” even though it’s not a sayornis .
if you have bird images , video or mp3 files that you ' d like to share with a large and ( mostly ) appreciative international audience here at the guardian , feel free to contact me to learn more .
the sharp whistled call of the black phoebe is a typical sound along creeks and ponds in the southwest . the birder who explores such areas is likely to see the bird perched low over the water , slowly wagging its tail , then darting out in rapid flight to snap up an insect just above the water ' s surface . related to the familiar eastern phoebe of eastern north america , this species has a much wider range , living along streams from california to argentina .
the black phoebe builds a nest out of mud . this mud nest is placed on a cliff , bridge , or building .
eastern phoebes made ornithological history in 1804 when john james audubon tied silver thread on the legs of nestlings - the first north american experiment in bird banding . the next year he found two of his marked birds nesting nearby .
weeks jr . , harmon p . 2011 . eastern phoebe ( sayornis phoebe ) , version 2 . 0 . in the birds of north america ( p . g . rodewald , editor ) . cornell lab of ornithology , ithaca , new york , usa .
the black phoebe needs a source of water . if there is water near your home you may be able to attract the black phoebe by planting appropriate plant material . they like trees , especially cottonwoods , for nesting and cover as well as a perch for hunting .
diet : black phoebe is mainly insectivorous . some birds are well adapted to capturing small fish . it may sometimes eat small berries .
unlike most songbirds who must hear other birds to hone their vocalizations , an eastern phoebe raised in isolation will still sing a perfect song .
the eastern phoebe ( sayornis phoebe ) is common everywhere in the u . s . that might even vaguely be considered the east , and other parts besides . this bird is almost certainly the most common flycatcher within its range . it is also one of the most recognizable with its rounded head and telltale tail pump . bigger than an empidonax flycatcher and smaller than a myiarchus , the eastern phoebe is usually only mistaken for a pewee , and even that becomes unlikely with experience . this phoebe of phoebes is considered a loner as far as its own kind is concerned , but doesn’t appear to mind human presence . in fact , this is one species that seems to thrive in the face of rampant development . because eastern phoebes are early migrants , they serve as a sweet harbinger of spring .
the eastern phoebe has a large range , estimated globally at 6 , 200 , 000 square kilometers . it is native to the nations of north america as well as belize , bahamas , cuba , and turks and caicos islands and prefers forest and shrubland ecosystems . the global population of this bird is estimated to be 16 , 000 , 000 individuals and it does not appear to meet population decline criteria that would necessitate inclusion on the iucn red list . the current evaluation status of the eastern phoebe is least concern .
hi heather , thanks for the information , it is much appreciated . my bird’s name is cheerio and he is about 2 week’s old now and he has almost all his feathers , he is a eastern phoebe , and i have had him for a week now . oh , and i was wondering about the ground beef , is there any special brand i need to get ?
i was watching a chickadee create a nest when i heard the phoebe calling . i have seen them very often , but never heard them !
the black phoebe is found west of the sierra nevada range below 4000ft . there is also a small pocket of summer residents in inyo county .
black phoebe responds with alarm calls and flights to birds of prey and corvidae which threaten nests . it may swoop down at terrestrial predators and snap bill .
nest under eve with four phoebe babies and babies died in nest fully feathered looking ready to fly . parent keeps coming to site , what would cause ?
the oldest known eastern phoebe was at least 10 years , 4 months old . it had been banded in iowa in 1979 , and was found in 1989 in alberta .
scientific name : sayornis phoebe . family : flycatcher . length : 7 inches . wingspan : 10 - 1 / 2 inches . distinctive markings : white throat , long dark tail and a dark head . nest : mud and moss , lined with grasses , hair and feathers , under a bridge , deck or in a cave entrance ; holds two to six white eggs . voice : calls its name in rapid successions , “phoebe , phoebe , phoebe . ” also , clear , whistled “weew” or “tiboo . ” habitat : near water , woods with streams , farmyards and along wooded country roads with bridges crossing streams . diet : insects . backyard favorites : native plants to attract bugs .
hi , just found few day old phoebe’s . i’m trying to get bugs into their tiny mouths – much more difficult than you’d think . any suggestions ? can i feed them worms ?
hi natalie , i just finished hand feeding 6 baby phoebes and i used kaytee exact hand feeding formula . you should be able to find it at any of your local pet supply stores , i just recently bought a container of it at petco . kaytee exact has all of the protein and nutrients that any baby bird needs . i am not sure how old your baby is but i use a small plastic syringe for feeding . good luck to you and your baby phoebe , let me know how it goes . heather : )
range : black phoebe breeds along pacific coasts , from southern oregon to central america into south america . it winters in most of breeding range , but northern populations may winter along gulf of california .
@ renee : i would suggest contacting a wildlife rehabilitator : if you google search you should be able to find one near you . i imagine that if you can’t get bugs into their mouths that chunks of earthworms can substitute until you can get the bird to a person who knows what they are about when it comes to raising birds .
the black phoebe is found in plant communities associated with water . they are almost always close to a water source . ( sometimes this water source can just be a lawn ) . they especially like cottonwoods
we have had the pleasure of having a black phoebe visit us every day for about the last two months . we have been feeding him mill worms . he will get very close , within 4 feet of us . he now calls us when we are indoors . on several occasions he has followed us to other friends homes . ( over 30 miles away ) our friends and relatives can not believe this is true , but we know it is . we feel very fortunate . he is a beautiful bird . please let me know if you have heard of this happening to others .
the use of buildings and bridges for nest sites has allowed the eastern phoebe to tolerate the landscape changes made by humans and even expand its range . however , it still uses natural nest sites when they are available .
black phoebe usually initiates flight from low perch after located prey , and it will pursue it until capture , in short and direct flight . it sallies from perch and hawks prey from the air , or gleans it from the ground or the water surface of a pond . it may skim floating insects on water . black phoebe rarely moves on ground , preferring to fly . it may occasionally land on ground near prey , and hop for capturing it .
to give you an idea of their foraging behaviour , here ' s a brief video of an eastern phoebe hawking insects ( filmed at north carolina museum of life and science , durham , nc . uploaded 9 may 2008 ) :
flight : black phoebe has direct flight with steady wing beats . it may hover while gleaning prey from various places , or within clouds of flying insects . it can perform some acrobatic flights with zigzags and spirals during flight displays .
hello , i am raising a baby phoebe . i have been feeding him soaked dog food and fly’s , but this morning he is not doing well . what do i feed him ? i have raised meney birds with the same thing .
the eastern phoebe’s eponymous song is one of the first indications that spring is returning . it’s also a great way to find phoebes as they go about their business in quiet wooded neighborhoods . just don’t mistake the black - capped chickadee’s sweet , whistled “fee - bee” call ; the phoebe’s is much quicker and raspier . during early summer , a great way to find phoebes is to quietly explore around old buildings and bridges . look carefully under eaves and overhangs and you may see a nest .
despite its unobtrusive behavior and drab coloration , the eastern phoebe is a familiar bird to those who live within its range . its tendency to nest on human dwellings and under bridges has endeared it to many and earned it the common names of
bridge pewee
and
barn pewee
in 19th century north america . indeed , this flycatcher ' s use of bridges has evidently been a key element in the spread of its breeding range into the great plains and the southeastern united states . unlike the barn swallow ( hirundo rustica ) , however , it has not totally abandoned its original nest sites and continues to nest on rock outcrops and other natural niches when available .
members of the tyrannidae occur in most types of forested and non - forest habitats in north america except for the tundra . some species such as the willow flycatcher and black phoebe are associated with wetland habitats , others like the olive - sided and hammond’s flycatchers need coniferous forests , and other species such as the cassin’s kingbird and say’s phoebe , occur in grasslands . related species often replace each other in different habitats or regions such as in the case of the eastern and western wood - peewees .
an eastern phoebe has just built her nest around a ten penny nail on my front porch . it just happens to be right over the step down into the yard . it took me a couple of days to determine the kind of bird she was since i am not very well educated about the different kinds of birds in my area . i was worried about where she built the nest , but my coming and going hasn’t seemed to deter her at all . she started spending the night in the nest even before she finished it completely . if i go out at night , she raises her head and watches me . i hope she continues to be tolerant of me .
sauer , j . r . , d . k . niven , j . e . hines , d . j . ziolkowski , jr . , k . l . pardieck , j . e . fallon , and w . a . link ( 2017 ) . the north american breeding bird survey , results and analysis 1966–2015 . version 2 . 07 . 2017 . usgs patuxent wildlife research center , laurel , md , usa .
call : typical call is a sharp tsip , similar to the black phoebe ’s . song : distinctive , rough whistled song consists of 2 phrases : schree - dip followed by a falling schree - brrr ; sometimes strung together one after the other .
heather . if the birds still need to be cared for and you know where the parents are , leave the nest there . the parents are not at all put off by the scent of humans , but they probably won’t approach the birds in your presence . if you’re going to try to feed them , consider corey’s suggestion above of ground beef . you should also consider contacting your local bird rehabilitation center for more information . good luck !
yes heather , cheerio is doing much better , he is learning to sit on my finger now and is eating like crazy , i started feeding him a different kind of dog food , so that could have made the difference . have you raised any other birds , i have raised , a starling , and some kind of sparrow ( we never knew what he was ) and a few others , and now cheerio . i could send you some photos of them if you want . if so my email is backonthetrail @ urltoken i wold love to send you some photos of my last bird ( he was a phoebe to ) he was crippled but he was special . i would love to keep in touch .
one of our most familiar eastern flycatchers , the eastern phoebe’s raspy “phoebe” call is a frequent sound around yards and farms in spring and summer . these brown - and - white songbirds sit upright and wag their tails from prominent , low perches . they typically place their mud - and - grass nests in protected nooks on bridges , barns , and houses , which adds to the species’ familiarity to humans . hardy birds , eastern phoebes winter farther north than most other flycatchers and are one of the earliest returning migrants in spring .
voice : sounds by xeno - canto black phoebe’s most common call is a “tsip” used all year round during flights , when foraging , or against nest predators . it is a sharp sound , more plaintive than eastern phoebe’s call . we can also hear a loud “tseee” . song is a four syllable sound , a rising “pee - wee” followed by other descending “pee - wee” . also a bright “pidl - eee” or “pi - ts - lee” repeated several times . chatter vocalizations are used when male approaches female and during sexual behaviour .
the eastern phoebe is a loner , rarely coming in contact with other phoebes . even members of a mated pair do not spend much time together . they may roost together early in pair formation , but even during egg laying the female frequently chases the male away from her .
flying insects make up the majority of the eastern phoebe’s diet . common prey include wasps , beetles , dragonflies , butterflies and moths , flies , midges , and cicadas ; they also eat spiders , ticks , and millipedes , as well as occasional small fruits or seeds . back to top
just curious…we just had our annual phoebe visitation . they raised 3 chicks , and left today or yesterday . where do they go ? are they in the neighborhood , teaching the young ones how to hunt ? or have they moved on to a summer home ? thanks , michael in maine
eastern phoebe : breeds in eastern north america , although its normal range does not include the southeastern coastal united states . migratory , winters from the ohio river to the gulf coast . very rare vagrant to western europe . preferred habitats include open woodland , farmland and suburbs , often near water .
pewees are darker and they have longer wings , but they are most easily separated from phoebes by the phoebes’ distinctive tail wagging . empidonax flycatchers have eye rings and wing bars , which are absent in the eastern phoebe . an empidonax flycatcher flicks its tail upward ; only the gray flycatcher dips its tail downward .
habitat : black phoebe favourite habitats are coastal cliffs , river banks , shorelines of lakes and ponds , creeks and streams , fountains in parks . it can be found from sea level to 3 , 000 metres of elevation . this species is associated with water , accompanied by source of mud required for nest construction .
behaviour : black phoebe sits and waits on exposed perches , waiting for preys . it takes prey in open areas and from air . it forages over grasslands , water , roads , gardens and parks . during breeding season , mates forage separately , male in open areas , and female inside and at canopy edge .
this phoebe is one of the earliest migrants to nest in the northern united states and southern canada , with pairs forming and building nests in late march in the southern reaches of its breeding range . a monogamous and typically double - brooded species , individuals usually keep the same mate for both broods . the unique character and scarcity of this phoebe ' s nest sites promotes strong site - attachment , so that the same pair occasionally occupies the same site in successive years¿a fact first documented by john james audubon in 1804 when he tied a small circle of silver thread to the legs of nestling phoebes and then documented their return in successive years .
most eastern phoebes winter in the southeastern united states , although some winter as far north as the lower midwest and as far south as mexico . severe winters in the southern united states may cause periodic population crashes of this species . although strongly insectivorous , this phoebe can subsist on fruits when cold , windy weather makes insects scarce .
because of its intimate association with humans and their edifices , there is a long history of anecdotal accounts and observational notes for the eastern phoebe . however , there is also a plethora of scientific studies , many focusing on aspects of reproductive biology and behavior . the earliest major work is that of klaas ( 1970 ) , in kansas , which is at the western limit of this phoebe ' s distribution ; yet other major works have followed in kansas , specifically those of murphy ( 1994 ) and schukman ( 1974 ) . weeks ( 1978 , 1979 ) conducted long - term studies in indiana ; conrad and robertson ( 1993a , b ) examined reproductive behavior in ontario , as did hill and gates ( 1988 ) in west virginia .
despite its plain appearance , this flycatcher is often a favorite among eastern birdwatchers . it is among the earliest of migrants , bringing hope that spring is at hand . seemingly quite tame , it often nests around buildings and bridges where it is easily observed . best of all , its gentle tail - wagging habit and soft fee - bee song make the phoebe easy to identify , unlike many flycatchers .
eastern phoebes are occasional , sometimes frequent , hosts , of the brown - headed cowbird ; that fact , coupled with the easy availability of nests , has led to several major investigations of cowbird / phoebe associations , beginning with klaas ( 1975 ) in kansas and followed by rothstein ( 1975 , 1986 ) in connecticut and michigan , and most recently hauber ( 2001 , 2003a , 2006 ) in new york .
hello , i accidently ended up with a nest full of baby black phoebes . there are six of them and i would say they are maybe a day to 2 days old . i tried putting the nest up high where it was originally but the parents never approached the babies again , so i started feeding them . i have baby bird food that i feed my baby cockatiels . now i am finding out that they are insect eaters , what do i do now ? what do i feed them an how do i care for them ? ? incubator ? ? do you think the parents would of eventually come around and fed them ? please , any info will be very much appreciated ! thank you , heather : )
this soft - voiced flycatcher of the west is like the other two phoebes in its tail - wagging habit ; but unlike them , it often lives in very dry country , far from water . it is typical of prairies , badlands , and ranch country , often placing its nest under the eaves of a porch or barn . in open terrain where there are few high perches , say ' s phoebe may watch for insects in the grass by hovering low over the fields .
i am so excited to have mr & mrs phoebe in my yard . we had a pond / waterfall put in last year and they have been visiting us since . and i think they like it because they have built a nest . up under an eave and hidden from all . made of mud and grass . i think she recently layed her eggs . i be keeping my eyes out for those little guys when they get here . and i think they are territorial because they chase other birds away from the pond . they think it’s theres alone . funny birds to enjoy in the backyard .
description : black phoebe is a small black and white flycatcher . adult has black upperparts , head and breast . belly and vent are white . wings show paler feathers’ edges . head , breast and upper back are rather sooty black . lower back , wings and tail are brownish slate . white colour on belly form an inverted v . dark tail shows white outer edges of external coverts . thin , pointed bill is black . eyes are dark brown . legs and feet are black . male and female show the same plumage , but during breeding season , male has cloacal protuberance and female has brood patch .
a black phoebe began visiting and perching on a chair near the pool several months ago . it seems to like hearing my voice , so i greet it each time it calls to me . it hasn’t followed us that i know of , but we were away for 5 days last week and when i put the kitchen blind up the morning after returning he came fluttering very close to the window in a more excited manner than usual . today , i heard him chirping and there he was perched very close to the window with a moth fluttering in his beak . almost as if he wanted to show me his catch .
thus best known aspects of this species ' life history are reproduction ( especially clutch size ) , nesting success , and impacts of nest parasitism . additionally , aspects of nestling growth ( stoner 1959 , mahan 1964 , murphy 1981 ) and behavioral displays and songs ( smith 1969 , 1970 ) are well described . in contrast , except for the work of beal ( 1912 ) and via ( 1979 ) , we know relatively little of the eastern phoebe ' s food habits and only a modicum about its energy budgets , relationships , and trade - offs . recently , substantial dna work has been done ( beheler 2001 ) , studies that have documented considerable extra - pair paternity and polygyny in this socially monogamous species .
reproduction : black phoebe female selects nest - site . nest is situated above water , and above high - water mark . nests situated above the ground are higher than others . nest may be found in dirt ledges along streams , sheltered places on large rocks over water , or in tree under broken branch , walls… female throws mud pellets onto vertical surface , in order to form a line , horizontal or upwards arc . then , she builds an open cup cemented with mud to a wall or other support . mud is mixed with grass , dry vegetation or hair . interior is lined with woven plant fibres , feathers and hair . it is usually situated under a ceiling , in a sheltered place , such crevices , ledges…
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any of various plants having pale flowers with dark centres , esp . t . . .
consider putting up a nest box to attract a breeding pair . make sure you put it up well before breeding season . attach a guard to keep predators from raiding eggs and young . find out more about nest boxes on our attract birds pages . you ' ll find plans for building a nest box of the appropriate size on our all about birdhouses site .
unlike most birds , eastern phoebes often reuse nests in subsequent years—and sometimes barn swallows use them in between . in turn , eastern phoebes may renovate and use old american robin or barn swallow nests themselves .
eastern phoebes breed in wooded areas ( particularly near water sources ) that provide nesting sites—typically human - built structures such as eaves of buildings , overhanging decks , bridges , and culverts . before these sites were common , phoebes nested on bare rock outcrops and still do occasionally . they seem to choose nest sites with woody understory vegetation nearby , possibly to make the nest site less visible or to provide perches near the nest for the adult . on migration they use wooded habitats and show somewhat less of an association with water . during winter , eastern phoebes occur in deciduous woods , more often near woodland edges and openings than in unbroken forests . back to top
eastern phoebes build nests in niches or under overhangs , where the young will be protected from the elements and fairly safe from predators . they avoid damp crevices and seem to prefer the nests to be close to the roof of whatever alcove they have chosen . nests are typically less than 15 feet from the ground ( in a few cases they have been built below ground level , in a well or cistern ) .
only the female builds the nest , often while the male accompanies her . she constructs the nest from mud , moss , and leaves mixed with grass stems and animal hair . the nest may be placed on a firm foundation or it may adhere to a vertical wall using a surface irregularity as a partial foundation . the female may at first need to hover in place while she adds enough of a mud base to perch on . nests can take 5–14 days to build and are about 5 inches across when finished . the nest cup is 2 . 5 inches across and 2 inches deep . unlike most birds , nests are often reused in subsequent years—and sometimes used by barn swallows in some years .
eastern phoebes sit alertly on low perches , often twitching their tails as they look out for flying insects . when they spot one , they abruptly leave their perch on quick wingbeats , and chase down their prey in a quick sally—often returning to the same or a nearby perch . less often , they hover to pick insects or seeds from foliage . phoebes rarely occur in groups , and even mated pairs spend little time together . males sing their two - parted , raspy song throughout the spring and aggressively defend their territory from others of their eastern phoebes , though they tolerate other species . both sexes , but particularly the female , attempt to defend the nest against such predators as snakes , jays , crows , chipmunks , mice , and house wrens . back to top
sibley , d . a . ( 2014 ) . the sibley guide to birds , second edition . alfred a . knopf , new york , usa .
population probably increased as buildings and bridges provided many more potential nesting sites . current numbers are apparently stable .
streamsides , farms , woodland edges . in breeding season , typically found near water in woodland or semi - open country . may be limited mostly by availability of good nest sites , which are often along streams . in migration and winter , found around edges of woods , brushy areas , often near water .
forages by watching from a perch and flying out to catch insects . most are caught in mid - air , some are taken from foliage while hovering briefly . also drops to the ground to pick up insects there . perches in shrubs or trees to eat berries .
4 - 5 , sometimes 2 - 6 . white , sometimes with a few dots of reddish brown . incubation is by female only , about 16 days . young : both parents bring food for nestlings . young usually leave nest about 16 days after hatching . adults typically raise 2 broods per year .
both parents bring food for nestlings . young usually leave nest about 16 days after hatching . adults typically raise 2 broods per year .
mostly insects , some berries . insects make up great majority of summer diet ; included are many small wasps , bees , beetles , flies , true bugs , grasshoppers , and others . also eats some spiders , ticks , and millipedes . small fruits and berries are eaten often during the cooler months , and are probably an important part of the winter diet .
male defends nesting territory by singing , especially at dawn . occasionally one male may have two mates , and may help to feed the young in two nests at once . nest : original sites were probably always on vertical streambanks or small rock outcrops in the woods , with a niche providing support below and some shelter above . now often builds nest under bridges , in barns , in culverts , or in other artificial sites . same site may be used repeatedly , and may build on top of old nest . nest ( built by female ) is an open cup with a solid base of mud , built up with moss , leaves , and grass , lined with fine grass and animal hair .
migrates quite early in spring and late in fall , especially compared to other flycatchers .
clear phoe - be , repeated many times ; the second syllable is alternately higher or lower than the first . call note a distinctive , short chip .
audio © lang elliott , bob mcguire , kevin colver , martyn stewart and others .
thanks to audubon vermont and others , the already green state is becoming even more proactive about preventing forest fragmentation .
tell congress to oppose a harmful rider that threatens sage - grouse and other wildlife .
numbers apparently stable , possibly increasing in some areas where artificial ponds have added to nesting habitat .
shady streams , walled canyons , farmyards , towns ; near water . occurs in a variety of semi - open habitats . rarely found away from vicinity of water , which may be natural streams or ponds , or irrigation ditches or even water troughs ; water ensures the availability of mud for nests .
forages by watching from a perch and darting out to catch insects , often just above water . catches insects in mid - air , or may hover while picking them from foliage or sometimes from water ' s surface . may also take insects from the ground , especially in cool weather . indigestible parts of insects are coughed up as pellets . male and female maintain separate feeding territories in winter .
4 , sometimes 3 - 6 . white ; some ( thought to be the last laid ) may have reddish - brown dots . incubation is by female only , 15 - 17 days . young : fed by both parents . may leave nest 2 - 3 weeks after hatching . usually 2 broods per year , rarely 3 .
fed by both parents . may leave nest 2 - 3 weeks after hatching . usually 2 broods per year , rarely 3 .
almost entirely insects . feeds on a wide variety of insects including beetles , grasshoppers , crickets , wild bees , wasps , flies , moths , caterpillars . occasionally eats small fish .
in courtship , male performs song - flight display , fluttering in the air with rapidly repeated calls , then descending slowly . nest : mud nests are usually plastered to sheltered spot such as cliff face , bridge support , culvert , or under eaves of building . occasionally in well a few feet below ground level . often returns to same nesting site year after year . nest ( probably built by female ) is an open cup , semi - circular if attached to vertical wall , circular if placed on flat beam . nest is made of mud mixed with grass and weeds , lined with soft materials such as plant fibers , rootlets , hair .
mostly a permanent resident , but departs in fall from highest elevations and from northern edge of range in southwest .
song is a thin , buzzy pi - tsee , usually repeated . call is a sharp , down - slurred chip .
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surprise ! i decided to give all of you a may day present ! fruit & flower enamel mugs are going to be available for pre - order tomorrow at 9am pst ! check my shop when the time comes : urltoken ! they will ship on / after may 12th .
image : pete myers , 2 march 2009 ( with permission ) [ velociraptorize ] . nikon d300 80 - 400mm f / 4 . 5 - 5 . 6 nikkor iso 320 focal length 400mm 1 / 500 at f / 6 . 3
eastern phoebes are consistently amongst the first migratory birds to arrive in the northeastern usa - - i ' ve seen them in central park in new york city in late march , which is at least three weeks before the first wave of neotropical migrants begins to arrive . they also are amongst the last migrants to leave in autumn .
eastern phoebes are fairly tolerant of humans and their structures , hence their alternative common names . this trait has probably contributed to the increase in this species ' population and range since historic times . however , these birds are not very tolerant of each other , and tend to spend most of their time alone , even when breeding .
you are invited to review all of the daily mystery birds by going to their dedicated graphic index page .
© 2018 guardian news and media limited or its affiliated companies . all rights reserved .
by downloading this nest box plan you will be subscribed to the cornell lab of ornithology and nestwatch enewsletters . you will receive a confirmation email with a link to complete subscription .
this species is in decline in certain regions . you can put up a nest box to help if you live in the right region and habitat .
place the platform close to overhead cover ( e . g . , overhangs , ledges ) .
copyright © 2018 cornell university cornell lab of ornithology 159 sapsucker woods rd ithaca , ny 14850 tel : 800 . 843 . 2473
adapts well to changes in landscape , often nesting in residential areas . numbers apparently stable .
scrub , canyons , ranches . found in open or semi - open terrain , often in dry country , avoiding forested areas . often in farmland , savannah , or prairie in south , dry upland tundra in northern part of range . unlike the other two phoebes , has no special attachment to vicinity of water .
forages by perching on low shrub or rock and darting out to capture insects . may catch its food in mid - air , or take it from low foliage or from ground . also often hovers low over fields until prey is spotted , then drops to ground to capture it . indigestible parts of insects are coughed up as pellets .
4 , sometimes 3 - 7 . white ; some ( thought to be the last laid ) may have small brown or reddish spots . incubation is by female only , 12 - 14 days . young : both parents bring food to nestlings . young leave nest about 14 - 16 days after hatching . 1 - 2 broods per year , sometimes 3 in the south .
both parents bring food to nestlings . young leave nest about 14 - 16 days after hatching . 1 - 2 broods per year , sometimes 3 in the south .
almost entirely insects . often feeds heavily on wild bees , wasps , winged ants . other insects in diet include beetles , moths , grasshoppers , crickets , and dragonflies . also eats spiders and millipedes , and occasionally eats berries .
males are thought to arrive on breeding grounds before females . male sings to defend nesting territory , usually from exposed perch , sometimes in flight - song display . nest site varies : on rocky ledge or crevices in cliffs or caves , in wells or mine shafts , under bridges or eaves ; occasionally in natural tree cavity or hole in bank . may take over old swallow nest . nest ( probably built by female , but details not well known ) is a flat open cup made of grass , weeds , moss , spiderwebs , wool , and other materials . unlike other phoebes , usually uses no mud in nest .
migrates north relatively early in spring . occasionally strays to atlantic coast ( once even to bermuda ) , mostly in fall .
the eastern is brownish gray above ; darkest on head , wings , and tail . its underparts are mostly white , with pale olive wash on sides and breast . fresh fall adult easterns are washed with yellow , especially on the belly . molt occurs on the breeding grounds . juvenile : plumage is briefly held and similar to the adult’s but browner , with 2 cinnamon wing bars and cinnamon tips to the feathers on the upperparts .
common . breeding : woodlands , farmlands , parks and suburbs ; often near water . migration : breeders return to the midwest mid - march–late april and depart late september–early october . rare in fall and winter to california . vagrant : casual west of the rocky mountains and northwestern great plains . accidental to southern yukon and northern alaska ; sight record for england .
bill , legs , and feet are black . feeds on insects , small fish , berries and fruit . weak fluttering bouyant flight .
song is a raspy
fee - bee
or
fee - b - b - bee
.
a group of flycatchers has many collective nouns , including an
outfield
,
swatting
,
zapper
, and
zipper
of flycatchers .
the passeriformes ( pronounced pas - ser - i - for - meez ) , a large taxonomic order that includes antbirds , cotingas , and flycatchers , is composed of one hundred eighteen families of birds .
the tyrannidae ( pronounced tie - ran - uh - dee ) , or tyrant flycatchers , is a very large , successful family of four hundred and twenty - four species in one hundred genera only found in the americas .
in north america , one hundred forty - seven species of tyrant flycatchers in fifty - eight genera have occurred . these include the brilliant vermillion flycatcher , the sassy kingbirds , and the bridge - loving phoebes .
some tyrant flycatchers are known for their bold , aggressive behavior , this family often called the tyrant flycatchers for this reason . the eastern kingbird in particular , seems to go out of its way to chase much larger birds ( such as turkey vultures ) away from its territory .
small to medium in size , tyrant flycatchers have stocky heads with medium sized beaks , tails that vary in length , and long wings . they also have short legs suited to their arboreal lifestyles .
tyrant flycatchers do not nest in colonies and mostly forage in pairs or alone although the eastern kingbird forms flocks during migration and on its wintering grounds in amazonia . most north american flycatchers share a similar foraging strategy that often varies by niche and prey item . this foraging strategy involves watching for insects from a perch , sallying out to catch one with a snap of the beak , and returning to the perch to eat it .
most tyrant flycatcher species have stable populations in north america . the olive - sided flycatcher , though , has sharply declined throughout its range possibly due to habitat destruction on its wintering grounds and has been listed as near - threatened .


phanaeus changdiazi is a species of beetle found in panama and costa rica .

it is named after franklin chang-díaz , a costa rican-american physicist and former nasa astronaut .

phanaeus changdiazi

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to cite this page : myers , p . , r . espinosa , c . s . parr , t . jones , g . s . hammond , and t . a . dewey . 2018 . the animal diversity web ( online ) . accessed at https : / / animaldiversity . org .
disclaimer : the animal diversity web is an educational resource written largely by and for college students . adw doesn ' t cover all species in the world , nor does it include all the latest scientific information about organisms we describe . though we edit our accounts for accuracy , we cannot guarantee all information in those accounts . while adw staff and contributors provide references to books and websites that we believe are reputable , we cannot necessarily endorse the contents of references beyond our control .
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clibanarius digueti is a species of hermit crab that lives off the western coast of mexico , and is abundant in the gulf of california .

it is known under various common names such as the mexican hermit crab , the blue-eyed spotted hermit or the gulf of california hermit crab .

clibanarius digueti

clibanarius digueti , a mexican hermit crab , aka the blue - eyed spotted hermit . to less than an inch in length .
key words : hermit crabs , clustering behavior , clibanarius antillensis , shell utilization .
palavras - chave : caranguejos ermitões , comportamento de agrupamento , clibanarius antillensis , utilização de concha .
harvey aw ( 1988 ) size and sex - related aspects of the ecology of the hermit crab clibanarius digueti bouvier ( decapoda : anomura : diogenidae ) . ph . d dissertation , university of arizona .
during interspecific foraging bouts in the presence of food odor only , c . digueti showed significantly more aggressive behaviors than p . perrieri ( w = 171 . 0 , p = 0 . 0015 ; table 2 ) , while p . perrieri showed significantly more submissive behaviors than c . digueti ( w = −92 . 0 , p = 0 . 0172 ; table 2 ) . c . digueti frequently initiated the interactions by approaching p . perrieri , and c . digueti escalated the interactions by frequently attacking and grasping p . perrieri ( table 2 ) . p . perrieri routinely responded to c . digueti ’s aggressive behaviors by retracting into their shells ( table 2 ) .
the number of aggressive ( u = 54 . 0 , p = 0 . 0019 ) and submissive ( u = 85 . 0 , p = 0 . 0295 ) behaviors were significantly higher for c . digueti than p . perrieri during intraspecific foraging bouts ( table 3 ) . the frequencies of all measured behaviors were higher for c . digueti than p . perrieri ( table 3 ) .
in the absence of a competitor , the feeding times of c . digueti and p . perrieri were not significantly different ( u = 102 . 0 , p = 0 . 6738 ; table 4 ) .
data were drawn from lab populations of c . digueti ( n = 75 ) and p . perrieri ( n = 79 ) following acclimation in housing tanks . wet weights were measured from animals after removal of their shells . lines represent best fit lines from linear regression analyses . c . digueti best fit line : y = 0 . 2442 x− 0 . 3584 . p . perrieri best fit line : y = 0 . 2472 x− 0 . 3764 .
during interspecific food competition , c . digueti fed for significantly more time than p . perrieri ( w = 179 . 0 , p = 0 . 0238 ; table 4 ) . differences in feeding times between the species can partly be explained by the fact that c . digueti was the first animal to contact and feed on the food item in 20 of the 26 trials analyzed ( χ 2 = 7 . 54 , df = 1 , p = 0 . 006 ) .
clibanarius tricolor , the blue - legged hermit crab . to less than an inch in length . one of a few
reef - safe
hermits that stay small and almost exclusively feed on algae ( and cyanobacteria ! ) . good for aiding in aerating the substrate as well . aquarium photo .
four hermit crab species were collected in the intertidal region of grande beach : clibanarius antillensis ( stimpson , 1862 ) , paguristes tortugae ( schmitt , 1933 ) , pagurus criniticornis ( dana , 1852 ) , and calcinus tibicen ( herbst , 1791 ) , with c . antillensis being the most abundant ( 226 individuals in 261 ) .
family hippidae ( sand crabs ) superfamily paguroidea , have oval carapaces , usually asymmetrical . live either in shells or with abdomen tucked underneath . first pair of legs as chelipeds . includes the hermit crab genera : pomatocheles , petrochirus , clibanarius , coenobita ( land hermit crab ) , pagurus , pylopagurus , birgus ( the coconut crab ) , stone crabs like lithodes , paralithodes ( commercial king crab of the north pacific ) .
the results of this study highlight the need for detailed field experiments measuring the importance of food competition in structuring hermit crab assemblages . while we can infer based on our laboratory results that the differences in competitive abilities between c . digueti and p . perrieri may have important ecological implications , detailed field experiments are needed to determine if the trends observed in the lab hold true in natural settings . it is our hope that the results presented in this manuscript will help raise awareness of the need for field experimentation .
these hermits crabs are often highly recommended as maintenance critters for marine aquariums , and can be bought as part of a
clean up crew
package . large groups need plenty of extra shells to accommodate for growth . these are some of the most popular hermits in the marine aquarium trade . since they are a
bread and butter
item and are collected in large numbers , prices are kept very low . other species of hermits may be sold as
red legs
, but c . digueti is by far the most common .
size - matched pairs of conspecific animals were tested using the same procedure listed in the previous section . one c . digueti trial was excluded from analyses because the animals switched shells during acclimation , and we could not be sure that subsequent aggressive behaviors were not shell - related . seventeen trials for each species were used for analyses ( 34 trials total ) . we compared the number of ( 1 ) aggressive , and ( 2 ) submissive behaviors shown between species during intraspecific trials using a two - sided mann - whitney u - test . paired tests were not required for these statistical analyses because the species were tested independently of each other , and thus the behaviors of one species could not directly affect the behaviors of the other .
neste trabalho são avaliados o comportamento de agrupamento de caranguejos ermitões bem como os padrões de utilização de conchas por indivíduos agrupados e isolados . o estudo foi desenvolvido na região entremarés da praia grande , são sebastião , sudeste brasileiro . as amostras foram feitas tanto com transectos quanto com quadrados de 1 m 2 aleatorizados durante períodos de maré baixa . os ermitões foram contados , medidos ( comprimento do escudo cefalotorácico ) e sexados . as conchas foram identificadas e avaliadas quanto sua adequação e condição ( danos físicos e incrustrações ) . os agrupamentos ocorreram principalmente em áreas expostas ao ar e foram dominados ou compostos unicamente por indivíduos de clibanarius antillensis . paguristes tortugae , pagurus criniticornis e calcinus tibicen também ocorreram nos agrupamentos , mas em menor abundância . um único agrupamento monoespecífico de p . criniticornis foi registrado em poças de marés . a grande maioria dos ermitões estavam inativos , com exceção de alguns indivíduos que estavam submersos em poças de marés . a maioria dos indivíduos c . antillensis estava agrupada ( 70 , 88 % ) . indivíduos isolados foram maiores que os agrupados e utilizaram principalmente conchas de tegula viridula , as quais mostraram - se mais adequadas para os ermitões dessa população . indivíduos agrupados usaram conchas menos incrustadas que os isolados . no geral , o comportamento de agrupamento de ermitões na praia grande apresentou os mesmos padrões de distribuição de tamanho e sexo e de utilização de conchas que os já descritos na literatura , embora o tamanho dos agrupamentos nessa área tenha se apresentado menor .
off the western coasts of mexico , and very common in the gulf of california .
these hermits are easy to care for . they are hardy and tolerate a wide range of water parameters . however , they cannot handle copper well . as with most invertebrates , even low levels of this me tal are enough to cause death . this hermit crab may attack snails or other hermits in order to steal the shells . for this reason it is important to provide a number of extra shells of various sizes , to allow for growth . this will prevent shell - related killings . aside from mechanical damage to corals caused by wandering specimens crawling over the polyps , red leg hermits will typically not bother aquarium residents .
these hermits will feed on detritus , green algae , shed exoskeletons , and dead organic matter . they are also happy to eat any food the keeper chooses to add to their tank , live or frozen , flake or pellet . they are claimed to consume cyanobacteria and hair algae , though this may not be true .
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about 42 , 000 species of some of the most familiar arthropods ; crabs , shrimps , lobsters , crayfish , wood - lice ( sow - bugs , rolly - pollies , you know , terrestrial isopods , and aquatic , even parasitic marine ones ) . many small members in fresh and marine habitats of importance in aquatic food chains . primarily aquatic , mostly marine .
behind the mandibles there are two pair of accessory feeding appendages , the first and second maxillae . 2 ) their bodies trunks are composed of distinct segments covered by a chitinous exoskeleton
. 3 ) crustacean appendages are typically biramous ( two major elements ) . 4 ) they typically have a carapace covering the trunk of their bodies . enough of this detail . we ' ll cover this stuff in more general survey pieces of the mega - groups . on toward the lobsters .
a systematic resume of the crustacea is necessarily large and complex . allow me to semi - skirt around a full discussion here . the nine classes that don ' t include our family of interest enclose the primitive cephalocaridans ( c . cephalocarida ) , the class branchiopoda ( fairy shrimps , tadpole shrimps , water fleas ( daphnia ) ; the class ostracoda , class copepoda ( anchor worm , lernaea ) , classes mystacocarida , branchiura , tantulocarida , remipedia , cirripedia ( barnacles ) , whew ! & finally , our :
comprises almost three - fourths of all described species of crustaceans and most of the larger forms , such as crabs , lobsters , and shrimps . characteristics : trunks typically composed of 14 segments plus the telson (
tail
) ; the first 8 segments form the thorax , the last 6 the abdomen ; all segments bear appendages . four superorders : syncarida , hoplocarida , peracarida , and the one we want to talk about , the eucarida .
superorder eucarida contains many of the large malacostracans . they have highly developed carapaces displaying fusion of all thoracic segments ( the cepahalothorax ) . eyes are stalked . . . two living orders ; the euphausiacea ( krill ) and the :
order decapoda includes the familiar shrimps , crayfish , lobsters and crabs . this is the largest order of crustaceans with @ 10 , 000 species . decapods are distinguishable from euphausiaceans and other malacostracans in that their first three pair of thoracic appendages , the remaining five pairs are legs ( decapoda =
ten feet
) . decapods are further divided into two suborders , the dendrobranciata , with
tree - like
branched gills , body laterally compressed . . . , eggs planktonic , nauplius as the first larval stage ( as in artemia , our brine shrimp ) , infraorders , sections , superfamilies . . . see barnes re their higher taxonomy .
of animals that are crabs (
false
and true ) there are about eight thousand described species , with about 600 venturing into or living in freshwater .
infraorder anomura , families of hermit crabs , sand or mole crabs , crab - like crustaceans . depressed carapaces , third pair of legs never chelate , fourth and fifth pair reduced . . . . have a soft abdomen . . . live with bodies enclosed in discarded shells for the most part .
best ( most
reef - safe
) hermit crab species ( though no carte - blanche guarantees ) for algae control : even these cannot be absolutely trusted with small fishes , invertebrates if hungry . . . and they too can be meals for . . . puffers , triggerfishes , stomatopods ( mantis ) , alpheids ( pistol shrimp ) . . .
calcinus laurentae haig & mclaughlin 1983 , laurent ' s hermit crab , family diogenidae . orange - yellow antennae . claw - limbs brown , other legs pink with white junctions and black tips . hawaiian endemic . common . to about 1 / 5
carapace length . kona pic .
calcinus tibicen , the orangeclaw hermit crab , family diogenidae . tropical west atlantic . orange antennae and eyestalks . eye tips white , eyes with black pupils . unequal size claws . 1 / 2 to 1
.
a common gulf of mexico hermit crab . very hardy . . . can live out of water for days at times .
* c . vittatus * does get rather large , 10 cm at least ( adam j . said he had one ( actually , he said it was * p . holthuisi * in a 6
shell )
scott allen rauch pic .
bigger pix : the images in this table are linked to large ( desktop size ) copies . click on
framed
images to go to the larger size .
paguristes cadenati forest 1954 , the scarlet or red - legged reef hermit . tropical west atlantic . to one inch in length . red carapace and legs , eyes green , on yellow stalks . aquarium and cozumel photo .
never entirely
reef safe
. . . all hermits are to degrees opportunistic omnivores . . . they will eat your other livestock if hungry . . . here two
, the red - banded hermit crab . tropical west atlantic . to four inches in length . claws about the same length with red spots or bands . antennae are golden , eyes blue .
paguristes puncticeps , the white speckled hermit crab . tropical west atlantic . to 5 inches in length . claws about the same length with red spots . blue eyes . white speckled eye stalks and body . cozumel 2017 image .
, the blue eye hermit crab . tropical west atlantic . to 2 . 5 inches in length . claws about the same length with red spots . small blue eyes on red speckled stalks .
phimochirus holthuisi , the red - striped hermit crab . tropical west atlantic . to one inch in length . one cheliped enlarged ( usually right ) ; movable pincer white . eyestalks white with dark band , eyes grayish blue .
trizopagurus ( ciliopagurus ) strigatus ( herbst 1804 ) , the striped or halloween hermit crab . indo - pacific and red sea . to a little over two inches in length . nocturnal . lives in empty cone shells . feed on live and dead animal material .
other species of hermits sometimes offered in the interest that are unusual , though not highly suitable for aquarium use .
manucomplanus varians ( benedict , 1892 ) , staghorn hermit . pix by sara mavinkurve . urltoken
other species of hermits sometimes offered in the interest that are trouble : for ( large ) fish - only systems .
aniculus hopperae mclaughlin & hoover 1996 , hopper ' s hermit crab . sometimes imported from hawai ' i . not a hardy aquarium species ; apparently a sponge feeder in the wild . to an inch in length . black eyes , yellow eye stalks , bright red claws bear black tips . hawaiian endemic . big island pic .
aniculus maximus , a large hermit crab . often imported from hawai ' i . to four inches in length .
dardanus gemmatus h . milne - edwards 1848 , jeweled anemone hermit crab . to two inches carapace length . with calliactis anemones on its shell . hawai ' i image .
dardanus lagopodes ( forsskal 1775 ) , the blade - eyed hermit crab . indo - pacific , including the red sea . to a little over two inches in length . white eye stalks , body mottled in maroon , brown , covered with white - tipped bristles . this one in aitutaki , cook islands and n . sulawesi .
dardanus megistos ( herbst 1789 ) , shell - breaking reef hermit crab , often sold as the white spotted . members of this genus are predaceous , and will gladly consume any fishes they can get their claws on . to six inches . place with large , aware fishes only . aquarium pic .
another reef hermit crab . indo - pacific . often with anemones placed on its movable home / shell . to a little over two inches in length . spiny chelipeds , red and white striped eye stalks are definitive . aquarium and n . sulawesi pix .
dardanus tinctor , a coral hermit crab . this one with its calliactis polypus anemones out at night in the red sea . to 10 cm . large left claw . nocturnal ; omnivorous . moves anemones when transferring to new shells .
dardanus venosus , the starry - eyed hermit crab . 3 - 5 inches . blue / green eyes , dark pupils that are star - burst like in close view . claws of lavender color generally . bristly . cozumel pic .
petrochirus diogenes , a giant hermit crab . to twelve inches ( not a mis - print ) . red / white banded antennae ; scale like covering of legs . blue / blue - green eyes . caribbean .
the superfamily paguroidea also includes stone crabs like lithodes , paralithodes ( commercial king crab of the north pacific ) .
if you use them , place about one , two small hermits per actual gallon of your system . use a mix of species and make sure and provide many
upgrade
homes ( empty shells ) for your hermits to move to .
baensch , hans & helmut debelius . 1994 . marine atlas , v . 1 . mergus , germany . 1215pp .
burgess , warren e . 1974 . salts from the seven seas ( on hermits ) . tfh 11 / 74 .
debelius , helmut . 1999 . crustacea of the world . atlantic , indian , pacific oceans . ikan , germany 321pp .
friese , u . erich . crustaceans in the home aquarium . hermit crabs . tfh 4 / 85 .
hoover , john p . 1997 . hawaiian hermit crabs , pts . i , ii . fama 9 , 10 / 97 .
jensen , christopher . 1998 . red legged hermit crab . fama 4 / 98 .
menten , bob . 1980 . the hermit crab . marine scavenger - par excellence . tfh 11 / 80
michael , scott . 1998 . hermit danger . some species of hermit crabs actually consider your fish their dinner . afm 5 / 98 .
general husbandry : these small hermit crabs are among the best at grazing algae , including slime algae .
keep in mind they do not have a shell of their own and therefore seek suitable size empty shells for protection , usually empty snail shells . the tip of their abdomen is then backed into the columella of the empty shell , calling it home . when danger exists , they retract further into the shell , disappearing from view . as they grow larger via the molting process in the wild , they must seek other slightly larger empty shells . its this process of living in someone else ' s shell that has led to their common name ' hermit , ' i . e . , a hermit living alone .
it ' s advisable to keep an assortment of different size empty snail shells in the aquarium when maintaining this species ( or any hermit ) , as they are very fussy about the space they have inside their selected shell and are always looking for something better / slightly roomier ! in fact , they often enter into battles with other hermits for their shells , with the loser either highly damaged or dead . they may also sometimes pick on live snails , however it is thought they are seeking the shell and not attacking the snail itself .
keep in mind they cannot tolerate copper treatments , therefore if they are in the same aquarium where fish need to be medicated with copper , they must be removed .
fyi : stocking level recommendations vary greatly for these little janitors / scavengers , e . g . , from 1 to 10 per gallon for reef aquariums . yet one should relate their need to the condition of the aquarium , as very well maintained systems need only a few in the entire system . overcrowded and / or overstocked systems no doubt need higher quantities . and new systems probably need none , as hermit nutritional needs will not be met until the aquarium ages somewhat .
in general , hermits can live for about 30 years in the wild , however , they don ' t last near that long in aquaria , with stays of about 1 - 2 years the average . keep in mind even though most hermits are born in the water , when molting they seek the land and bury themselves for protection from predators . depending on their age , the molting process can occur from once a month to once every 18 months , with the process taking about 10 days to complete . therefore , their lifespan in aquaria is questionable / quite limited .
the material on this site may not be reproduced , distributed , transmitted , cached or otherwise used , except with the prior written permission of bob goemans .
lemaitre , r . ; mclaughlin , p . ( 2018 ) . world paguroidea & lomisoidea database .
mclaughlin , p . a . ; komai , t . ; lemaitre , r . ; listyo , r . ( 2010 ) . annotated checklist of anomuran decapod crustaceans of the world ( exclusive of the kiwaoidea and families chirostylidae and galatheidae of the galatheoidea . part i – lithodoidea , lomisoidea and paguroidea . the raffles bulletin of zoology . supplement no 23 , 5 - 107 . [ details ] available for editors [ request ]
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mix and match to save ! quantity discount applies to all eligible saltwater hermit crabs and snails on your order . the red leg hermit crab is an excelle . . .
care level : easy temperament : peaceful reef compatible : with caution water conditions : 72 - 78° f , dkh 8 - 12 , ph 8 . 1 - 8 . 4 , sg 1 . 023 - 1 . 025 max . size : 1
diet : herbivore supplements : calcium , magnesium , iodine , trace elements
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conceived and designed the experiments : mvt rwh . performed the experiments : mvt mo jc kvn . analyzed the data : mvt . wrote the paper : mvt mo jc kvn rwh .
, which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited .
this research was funded by the dr . marvin hensley endowed scholarship in zoology awarded to mark v . tran by the zoology department at michigan state university . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .
this study used only invertebrate animals , which are not regulated by the institutional animal care and use committee at michigan state university .
following gender determination , animals were housed in small groups in plastic containers ( 20×13×14 cm or 26×16×17 cm ) containing asw and a gravel substrate for a minimum of 4 days to allow sufficient time to recover from handling stress . because we allowed a minimum of 4 days to recover from handling stress , it is highly unlikely that the different methods of sex determination used between species influenced the animals’ behaviors in our experiments . this , however , was not empirically tested . the size of the containers used to house experimental animals had no effect on either species for any of the measured behaviors ( mann - whitney u - tests , p > 0 . 05 ) .
relationship between wet weight ( g ) and shell length inhabited ( cm ) .
for experiments assessing feeding times in the absence of a competitor , we used animals of both sexes ( 11 males : 4 non - gravid females of each species ) that had previously been used in other behavioral experiments and were randomly drawn from mixed - species population tanks . we did this because we had a limited availability of p . perrieri males and had no a priori reason to believe that normal feeding behaviors ( 1 ) would be affected by the animals’ previous use in other experiments , or ( 2 ) differed between sexes when no competitors were present .
the testing apparatus consisted of a 250 ml glass erlenmeyer flask ( 8 cm bottom diameter ) containing 250 ml of asw and clean , white gravel substrate . this apparatus was large enough that the test animals could remain physically separated and were not forced to interact .
this experiment was done to determine if feeding times for both species were similar in the absence of a competitor . the same experimental procedure was used as explained in the previous section , except that only a single animal was placed in the apparatus during each trial . feeding times were compared between species using a two - sided mann - whitney u - test .
total counts of behaviors shown . counts were summed among test animals of the same species . n = 20 trials .
total counts of behaviors shown . counts were summed among test animals of the same species . n = 17 trials for each species .
feeding times when species fed together ( with competition ) and independently ( without competition ) .
we thank n . ostrom , g . mittelbach , and w . li for assistance and guidance on the planning of this study , and b . wagner for assistance with acquiring research animals .
sur quelques crustacés anomures et brachyures recueillis par m . diguet en basse - californie
sur une collection de crustacés décapodes recuellis en basse - californie par m . diguet
bouvier ( decapoda : anomura : diogenidae ) . ph . d dissertation , university of arizona .
because of the sheer size of our forum , we ' ve been forced to limit selling and trading to members who ' ve met a couple of criteria . ( if you ' re seeing this message , you haven ' t met them yet . ) please take a moment to acquaint yourself with our selling / trading rules to help make your stay a long and rewarding one .
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ i ' m not a noob , i just buy fish with a short life span . . . current tank info : 100 gallon plexy with 35 gallon sump
good to hear the frags are taking to the rubble , softies are always a little challenging . give them a little more time before you move them . thanks for the tip but i don ' t have any cyano bacteria in my tank . i do have some red turf algae , but there is a big difference . cyano is a living indicator of high nutrient levels and / or not enough flow . ultimately you want to address those issues and the cyano will dissapear and not come back . regarding hermits , i ' m not too fond of them . i much prefer snails which they will kill , it ' s only a matter of time . also be cautios with anything from mexico - the water there is temperate and unless you can maintain cool temps the critters won ' t live long .
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ jacob . current tank info : retired from reefing . . .
jake , u still have that turf agae ? did the seahare and / or phosphate absorbant stuff make any dent ? yeah the little hermit crabs can kill snails but they are also fun to watch . scott
i ' ve lost 2 snails so far out of about 9 months and still have about 4 left . seems they only get picked on when my largest hermit desides he needs a
home upgrade
. they didn ' t have a picture of the algae so wasn ' t sure if it was the same but the description was dead on so i figured i ' d give it a post . i ' ll keep an eye out .
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turra , a . 1 , 2 and leite , f . p . p . 1
departamento de zoologia , ib , unicamp , c . p . 6109 , cep 13083 - 970 , campinas , sp , brazil
programa de pós - graduação em ecologia , ib , unicamp , c . p . 6109 , cep 13083 - 970 , campinas , sp , brazil
correspondence to : alexander turra , departamento de zoologia , ib , unicamp , c . p . 6109 , cep 13083 - 970 , campinas , sp , brazil , e - mail : turra @ urltoken
hermit crabs display clustering behavior and daily movements ( hazlett , 1966 ; snyder - conn , 1980 ; gherardi & vannini , 1989 , 1992 and 1993 ) which are closely related to the tidal rhythm ( snyder - conn , 1980 ) . clusters are tipically formed during low tides when the hermit crabs stay in physical contact with each other , presenting low activity and preference for shady substrates ( snyder - conn , 1980 ) . at flood tide the hermit crabs disperse to foraging areas and present social activities ( gherardi & vannini , 1993 ) , while at high tide they remain generaly inactive under boulders and in crevices ( snyder - conn , 1980 ) . low and high tides are considered adverse periods due to the risks of desiccation and predation , respectively ( snyder - conn , 1980 ) , thus also leading the hermit crabs to look for refuges .
the clustering behavior is probably controlled by interactions between exogenous and endogenous factors related to the tidal cycle . in this way , environmental stimuli ( air exposure , hydrostatic pressure , light , food availability and small scale water movements ) seem to play an important role in determining the activity of the hermit crabs ( snyder - conn , 1980 ; gherardi & vannini , 1989 ) . the adaptative meaning of the clustering behavior was largely investigated by gherardi & vannini ( 1992 , 1993 ) . it is supposed that clusters serve as
shell exchange markets
or places were males and females can locate themselves easily . however , clustering may be a response to environmental factors , such as desiccation ( reese , 1969 ; gherardi & vannini , 1993 ) , and habitat heterogeneity ( snyder - conn , 1981 ; turra et al . in press ) .
the aim of this study was to describe the clustering behavior of hermit crabs in the brazilian coast , focusing cluster size ( number of individuals per cluster ) , species composition , and shell utilization pattern . comparisons of populational parameters and shell adequacy and condition between clustered and scattered individuals were used as evidences to discuss theories on the factors that regulate the clustering behavior in the area of study .
this study was conducted from september to december 1994 at the grande beach ( 45 o 24 ' w ; 23 o 49 ' s ) , são sebastião , northern coast of são paulo state , brazil . the area of study is an intertidal habitat of 160 m 2 composed by cobbles and boulders irregularly arranged forming natural refuges , holes and crevices . the tides are semidiurnal with maximal variation of 2 meters .
twenty two quadrats of 1 m 2 were sorted in the area of study in order to evaluate the dispersion pattern and the activity of the hermit crabs during low tide . a dispersion index was calculated to access the pattern of distribution of hermit crabs ( elliott , 1977 ) . active individuals were those that were feeding or walking . each quadrat was characterized in relation to air exposure ( total or partial ) or submersion ( presence of tide pools ) . hermit crabs and their shells were identified and the number and size of clusters ( number of individuals present in each cluster ) were registered . shell adequacy and condition were also evaluated .
the shell adequacy to the hermit crabs was evaluated using a visual index modified from abrams ( 1978 ) : 1 . hermit crab not visible ; 2 . pereopods visible but chelipeds not ; 3 . angle of 90 o between chelipeds and the plan of the shell aperture ; 4 . obtuse angle between chelipeds and the plan of the shell aperture ; 5 . chelipeds closing the aperture ; 6 . shield exposed . the shell condition was recorded using a modification of the condition index proposed by mcclintock ( 1985 ) . this index evaluates the degree of incrustation ( 1 . shell not incrusted ; 2 . until 50 % incrusted ; 3 . 50 % to 100 % incrusted ) and of physical damage in the shells used by the hermit crabs ( a . perfect ; b . perforations and / or less than 4 mm of the aperture damaged ; c . more than 4 mm of the aperture damaged and / or apex broken ) .
in order to compare the size distribution between clustered and scattered individuals , three 0 . 50 m wide transects were sampled during the low tide . the crabs were classified as clustered ( 5 or more individuals ) or scattered , removed from their shells , and sized ( shield length ) with a milimetric ocular under stereomicroscope . cluster size was also recorded . the two - way anova and the log - likelihood g test were both performed with a 0 . 05 significance level ( zar , 1984 ) .
the dispersion pattern of the crabs was contiguous ( i = 621 . 130 , d = 28 . 84 , df = 21 , p < 0 . 001 ) , and greatly influenced by the distribution of c . antillensis . most of the hermit crabs were present in clusters ( 70 . 88 % , g [ 1 ] = 46 . 96 , p < 0 . 001 ) , that were more frequently found in air exposed areas ( 14 clusters out of 15 ) . most of the aggregates ( 11 ) were monospecific , composed only by individuals of c . antillensis ( 10 ) or of p . criniticornis ( 1 cluster composed by 6 individuals in a tide pool ) . polyspecific clusters were dominated by c . antillensis but also presented individuals of p . tortugae , p . criniticornis and / or c . tibicen . the clusters composed or dominated by c . antillensis presented 5 to 42 individuals ( n = 14 , 12 . 78 ± 10 . 29 individuals ) .
the activity pattern of the hermit crabs was studied only during low tide . scattered and clustered individuals exposed to the air were inactive , differently from some isolated and submerged ones ( 3 individuals ) in tide pools . some isolated hermit crabs , exposed to the air and out of refuges , presented their shells with the aperture turned upward .
in the transects 31 males and 27 females ( 14 ovigerous , 44 . 44 % ) of c . antillensis were collected ( table 1 ) . both males and females were more frequently found in clusters than isolated ( females : g [ 1 ] = 14 . 85 , p < 0 . 001 ; males : g [ 1 ] = 3 . 98 , p < 0 . 05 ) . size showed to be more dependent on the behavioral situation of the crabs ( clustered or scattered ) than on their sex , although males were sligthly larger than females ( table 1 ) .
shell utilization differed between clustered and scattered individuals of c . antillensis ( g [ 5 ] = 262 . 14 , p < 0 . 001 ) ( fig . 1 ) . shells of tegula viridula ( gmelin , 1791 ) were more frequently occupied by scattered individuals , while shells of stramonita ( = thais ) haemastoma ( linnaeus , 1797 ) , morula nodulosa ( c . b . adams , 1845 ) , leucozonia nassa ( gmelin , 1791 ) , and cerithium atratum ( born , 1778 ) were used mainly by the scattered ones .
shell adequacy and incrustation also differed between clustered and scattered individuals ( table 2 ) . shells were more adequate and incrusted for isolated than clustered crabs .
physical damage did not show any relationship with the behavioral situation ( clustered or scattered ) of the crabs ( table 2 ) . shell adequacy also seemed to be dependent on the shell type ( g [ 16 ] = 33 . 65 , p = 0 . 006 ) , with shells of t . viridula and c . atratum presenting better adequacy than shells of s . haemastoma , l . nassa , and m . nodulosa ( fig . 2 ) .
as expected , all hermit crabs that were exposed to the air were inactive , even those that were clustered and in refuges . at low tide the hermit crabs store water inside their shells and occupy moist microhabitats to avoid the lack of oxygen and the risks of desiccation ( gherardi et al . , 1989 ) . inactive and scattered individuals of c . antillensis presented the aperture of their shells turned upward . this behavior results in a higher retention of water inside the shell as suggested by reese ( 1969 ) , thus enhancing their resistence to long time exposure periods . active individuals were registered only in tide pools . in this way , the activity pattern can be related to the easier locomotion in water due to the lightening of the shells ( gherardi et al . , 1989 ) , and to the physical stress imposed by the air exposure situation .
scattered individuals of c . antillensis were larger than clustered ones , as also showed in other studies with other species ( hazlett , 1966 ; gherardi & vannini , 1989 ; gherardi , 1991 ) . small individuals have a greater surface / volume ratio and are more susceptible to desiccation than the large ones ( gherardi & vannini , 1992 , 1993 ) . thus , clustering might also serve to reduce the risk of desiccation as also suggested by reese ( 1969 ) and snyder - conn ( 1981 ) .
both males and females of this c . antillensis population occurred mainly in clusters , and 44 , 44 % of the females were ovigerous . these results support the hypothesis that clusters may serve as places where males can easily find females ( gherardi & vannini , 1992 , 1993 ) . in addition , clustering may also protect ovigerous females and their eggs from desiccation .
the pattern of shell utilization of hermit crabs is frequently associated with shell availability as can be seen in this area ( leite et al . , 1998 ) , with c . antillensis occupying mainly shells of tegula viridula . however , scattered individuals of c . antillensis used shells of t . viridula in higher frequencies than do clustered ones , probably because these shells presented higher adequacy than the others , as also recorded in other studies ( gherardi , 1991 ; gherardi & vannini , 1993 ) . in addition , shells used by the scattered individuals of c . antillensis presented better adequacy , and higher incrustation and adequacy than that used by the clustered supporting the hypothesis that clusters may serve as
shells exchange markets
( gherardi & vannini , 1993 ) .
the small size of clusters in this area also seemed to be associated with the high availability of empty gastropod shells in this area ( leite et al . , 1998 ) . in this way , a high shell availability may indicate a good shell adequacy to this population , thus not forcing the crabs to look for new ones in dense aggregations .
the meaning of the clustering behavior is still controversal and doubtfull . it is more parsimonious and reasonable to think that many selective forces , such as shell limitation ( behavioral factor ) and environmental stress ( physical factor ) are influencing together the clustering behavior in hermit crabs . to evaluate the role of each factor in the cluster formation it is needed a fully experimental study , isolating all possible factors to test one each time .
acknowledgments  we wish to thank fapesp ( fundação de amparo à pesquisa no estado de são paulo ) by the fellowship n o 93 / 2439 - 4 , and cebimar - usp ( centro de biologia marinha da universidade de são paulo ) for logistic support . giuliano buzá jacobucci and antônio carlos cruz macedo revised the manuscript .
elliott , j . m . , 1977 , some methods for the statistical analysis of samples of benthic invertebrates .
hazlett , b . , 1966 , social behavior of the paguridae and diogenidae of curaçao .
leite , f . p . p . , turra , a . & gandolfi , s . m . , 1998 , hermit crabs ( crustacea , decapoda , anomura ) , gastropod shells and environmental structure : their relationship in southeastern brazil .
snyder - conn , e . , 1980 , tidal clustering and dispersal of the hermit crab
snyder - conn , e . , 1981 , the adaptive significance of clustering in the hermit crab
turra , a . , jacobucci , g . b . , araújo , f . m . p . & leite , f . p . p . ( in press ) , spatial distribution of four sympatric species of hermit crab ( decapoda , anomura ) .
r . bento carlos , 750 13560 - 660 são carlos sp - brazil tel . / fax : + 55 16 271 - 5726 bjb . iie @ urltoken
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mark v . tran , 1 , 2 , * matthew o’grady , 1 jeremiah colborn , 1 kimberly van ness , 1 and richard w . hill 1 , 2
this is an open - access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are properly credited .
to test aggression and competitive abilities , we sized - matched pairs of animals . these pairs of animals were always drawn from separate plastic housing containers in order to alleviate the effects of any pre - existing dominance hierarchies that may have been formed among tankmates
. for all experiments assessing interspecific differences , we housed animals in containers with conspecifics only , and for experiments assessing intraspecific differences , we housed animals in mixed - species containers . on the day the experiments were conducted , experimental pairs of animals were formed by selecting one animal from separate containers . all pairs of animals were size - matched within 3 mm shell length . size - matching controlled for the effect of body size on aggression and competitive abilities . shell length was used as a proxy for body size because ( 1 ) the species show similar relationships between wet body weight ( g ) and length ( cm ) of shell inhabited (
, and ( 3 ) using animals of equal shell size helped to ensure that aggressive interactions observed during the trials were the result of food competition , and not the result of motivation to switch shells , which could confound the results of these experiments . this method was effective since test crabs rarely showed shell investigation behavior , and only one case of shell switching was documented during the trials . both species routinely occupied
shells . we did not assay for differences in behavior based on shell species occupied .
animals were given no food for 2 days prior to use to ensure motivation to forage during trials . on the day of the experiment a size - matched pair of heterospecific animals was formed , placed into the testing apparatus , and given a minimum of 15 minutes to acclimate . following acclimation , 2 ml fe were pipetted into the top of the apparatus using a glass pipette . the animals were allowed 30 seconds to initiate foraging behaviors , after which the numbers of aggressive and submissive behaviors (
) exhibited by each animal were counted for 10 minutes . only trials in which both animals showed obvious foraging behaviors ( e . g . , increased locomotion , substrate probing , feeding movements )
after the fe was introduced were included in analyses . this ensured that the animals were motivated to forage and in a healthy physiological state during the trials . twenty trials of this experiment met these criteria and were used for analyses . we compared the number of ( 1 ) aggressive behaviors , and ( 2 ) submissive behaviors observed during the trials between the species using a two - sided wilcoxon sign - ranks test for matched pairs . paired analyses were required because the behaviors of one species could directly influence the behaviors of the other species during the trials . these , and all other statistical tests mentioned in this report , employed a significance cutoff of