barbour 's map turtle ( graptemys barbouri ) is a species of turtle in the family emydidae .

the species is endemic to the southeastern united states .

barbour ' s map turtle

the barbour’s map turtle is protected as a state threatened by florida’s endangered and threatened species rule .
false map turtle - g . pseudogeographica - mississippi map turtle - g . p kohnii - false map turtle - g . s p pseudogeographica
there are no known adverse effects of barbour ' s map turtles on humans .
barbour ' s map turtle is a great turtle for a community habitat with mud turtles , musk turtles , sliders , cooters , other map turtles and painted turtles .
barbour ' s map turtle is classified as vulnerable ( vu ) on the iucn red list ( 1 ) .
barbour ' s map turtles aren ' t known to have any negative impacts on humans .
all barbour ' s map turtles are carnivorous . females eat only mollusks as adults , primarily
barbour ' s map turtle nests are subject to predation by snakes and terrestrial mammals , such as raccoons . humans sometimes consume barbour ' s map turtles as food . barbour ' s map turtles are capable of withdrawing into their shells as well as trying to bite if they are unable to escape danger .
information on barbour ' s map turtle ( graptemys barbouri ) is currently being researched and written and will appear here shortly .
barbour ' s map turtles are carnivores , so they only eat other animals . females eat mostly
the most popular ones were the sabine map turtle ( graptemys ouachitensis ) and the false map turtle ( graptemys pseudogeographica ) – including the subspecies mississippi map turtle ( graptemys pseudogeographica kohni ) .
barbour ' s map turtles are important predators of mollusks and they and their eggs get eaten by other predators .
barbour’s map turtle is largely limited to clear , limestone - bottomed streams that contain numerous fallen branches and trees . highly aquatic , it spends much time basking on logs , plunging into the water when disturbed . the barbour’s map turtle feeds only in water , and , except when nesting , rarely travels far from shore .
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plastron on adult northern map turtle . picture by d . gordon e . robertson
. females usually live in deeper water than males . young barbour ' s map turtles stay closer to the riverbank than adults .
breeding interval barbour ' s map turtles breed annually , and females are capable of producing multiple clutches in a single mating season .
uncommon : rio grande cooters , barbour’s map , pacific pond , western chicken turtle , loggerhead musk , stripe - neck musk , yellow mud ( hatchling ) , florida mud .
240 gallon aquarium – larger female cooters ( particularly river cooters ) , female barbour’s map , larger female spiny softshells , common snappers .
there has been some concern in recent years about map turtles in the wild , and the loss of suitable map turtle habitats .
krysko , k . , k . enge , and p . moler . 2011 . graptemys barbouri carr and marchand 1942 barbour’s map turtle . atlas of amphibians and reptiles in florida .
hill , e . pierson and jonathan d . mays . 2016 . geographic distribution : graptemys barbouri ( barbour ' s map turtle ) . herpetological review 47 ( 1 ) : 79
mays , jonathan d . and e . pierson hill . 2016 . geographic distribution : graptemys barbouri ( barbour ' s map turtle ) . herpetological review 47 ( 1 ) : 79
the area where barbour ' s map turtles generally live and travel is 365 meters along the river for males and 273 meters for females .
sanderson r a ; lovich j e 1988 . graptemys barbouri carr and marchand barbour ' s map turtle . catalogue of american amphibians and reptiles ( 421 : 1 - 2 - get paper here
the barbour’s map turtle lives in clear flowing rivers found in florida , georgia and alabama . often spotted basking in the sun on top of rocks and snags , the turtle will dive into the water when threatened . in this turtle species , females grow to more than double the size of males .
how often does reproduction occur ? barbour ' s map turtles breed annually , and females are capable of producing multiple clutches in a single mating season .
sanderson , r . a . 1974 . sexual dimorphism in the barbour’s map turtle , malaclemys barbouri ( carr and marchand ) . master of arts thesis , university of south florida , tampa . 94pp .
sterrett , sean c . , john b . jensen and brian folt . 2014 . graptemys barbouri ( barbour ' s map turtle ) basking height . herpetological review 45 ( 2 ) : 314 - 315
in the wild , female barbour’s map turtles feed almost entirely upon fresh water mussels , snails and crayfish . males take smaller snails , insects , crayfish , and fish .
barbour’s map turtles live in the southeastern united states . they live in alabama , georgia , and the florida panhandle , in and around the apalachicola and the chipola rivers .
barbour ' s map turtles are important predators of mollusks in the areas the inhabit and are preyed on by other predators as eggs , young , and sometimes as adults .
the florida fish and wildlife commission is accepting comment , and holding webinars regarding proposed guidelines for managing the crayfish , pine snake , barbour’s map turtle , blackmouth shiner , saltmarsh topminnow , big cypress fox squirrel and florida burrowing owl .
it is found in the pascagoula river in the united states . it formerly included a population in the pearl river , but in 2010 , that population was described as a separate species , the pearl river map turtle , graptemys pearlensis . the pascagoula map turtle shares its range with the yellow - blotched map turtle , g . flavimaculata .
scientists don ' t know much about how barbour ' s map turtles communicate or sense their environment . in courtship , males touch the faces of females with their front legs .
males engage in a courtship routine in which they touch the face of females with their legs , but communication and perception are otherwise largely unknown for barbour ' s map turtles .
barbour ' s map turtles are considered
vulnerable
by the iucn and are on appendix iii of cites . they are given a global rank of
g2 ,
indicating that the species is imperiled . barbour ' s map turtles have a relatively restricted range and are subject to threats to their freshwater ecosystems , including dredging , water impoundment , and pollution .
connor , p . 1993 . cagles map turtle . tortuga gazette , ( 29 ) 10 : 1 - 4 .
fairly easy to acquire : ybs , peninsula cooter , texas map , ouchita map , false map , diamondback terrapin ( as a group ; specific subspecies may be harder to track down ) , razorback musk , mississippi mud , spotted turtle , north american wood turtle , common snapper , alligator snapper .
if you keep your map turtle outside , a heat lamp map can still be used and may even be necessary depending on where you live . if you live in an area where it gets too cold at certain points of the year , an outdoor pond may not be the best choice for your map turtle .
cagle ' s map turtle ( graptemys caglei ) from the guadalupe and san antonio rivers in south central texas , is an ornately patterned species that reproduces well in captivity . as with many map turtle species , there is extreme sexual dimorphism in cagle ' s map turtles . adult females typically reach 10 - 12 inches as adults and males mature at 4 inches and rarely reach more than 5 inches .
males of some map turtle species do not exceed four inches in length even in adulthood limiting their availability in the pet trade .
scientists don ' t know much about how long barbour ' s map turtles live in the wild . the record for the longest lifespan in captivity was 31 years , 8 months , and 9 days . this turtle lived at the national zoo in washington , dc .
having too little exposure to direct sunlight can negatively impact your map turtle’s health . sunlight deprivation can cause problems with their shell and even fungal infections . if your map turtle is in an outdoor pond , make sure some of its basking areas have access to direct sunlight at any point during the day . if you keep your map turtle in an indoor tank , make sure you have a high quality lamp that simulates the sun’s rays . you may have to take your turtle outside occasionally if the lamp doesn’t seem to be doing enough .
5 common map turtles , or northern map turtles as they are more correctly called . picture by d . gordon e . robertson
the false map turtle ( graptemys pseudogeographica ) is found from southern minnesota , wisconsin , and southeast to louisiana and texas . they do not have the broad , muscular heads seen in many map turtle species due to their diet which consists almost entirely of insects and insect larvae instead of crustaceans and mollusks seen in other map turtles . female false map turtles reach 9 inches and males reach 5 inches .
it might be illegal to take a map turtle from the wild in your area . make sure to research what the regulations are in your area before considering catching a wild turtle to keep as a pet .
there is no information about the lifespan of barbour ' s map turtles in the wild . the longest observed lifespan in captivity was 31 years 8 months and 9 days at the national zoo in washington , dc .
2 . ) pacific pond turtle - actinemys marmorata ( 2 subspecies ) ( note : formerly clemmys marmorata , ' western ' pond turtle ) .
ewert , m . a . , p . c . h . pritchard , and g . e . wallace . 2006 . graptemys barbouri – barbour’s map turtle . pages 260–272 in p . a . meylan , editor . biology and conservation of florida turtles . chelonian research monographs no . 3 .
barbour ' s map turtles are considered
vulnerable
by the iucn red list and are listed on on appendix iii of cites . their global rank is
g2 ,
which means that they are at risk . barbour ' s map turtles live in a fairly small area . they are threatened by damage to their habitat , which can come from from machines moving sand from the bottom of the river , interfering with the flow of water , or pollution .
like many reptiles , barbour ' s map turtles do not put much time or effort into caring for the young . females dig a nest and cover the eggs with dirt . besides that , neither parents contribute to the survival of their young .
barbour ' s map turtles spend most of their lives in the water , so they are good swimmers . males spend more time in calmer water , probably because they are smaller . barbour ' s map turtles spend a lot of time warming themselves in the sun , especially on limestone rocks , vines , or trees in or near the water . if there is a flood in the stream and river where they live , they move to the spot in the river with the weakest current .
try to maintain a high concentration of oxygen in your map turtle enclosure . you can add lots of extra aquatic plants and use a larger - than - expected filtration unit . by keeping oxygen levels high and ph levels appropriate for the species , you will prevent many of the problems normally encountered by map turtle keepers .
some of the species ( such as the barbour’s map turtle ) have a few juts coming out of the top of their shell , resembling a line of dorsal fins . some also have spike - like juts coming out around the base of their carapace . this helps add to their interesting appearance that makes them desirable to some potential pet owners .
other map turtles , while smaller , exhibit a wide array of carapace “decorations” , colors and habits . you can read more about some of these in the articles linked below . pictured here is the spectacular ringed map turtle ( g . oculifera ) .
because barbour ' s map turtles spend most of their lives in the water , they are good swimmers . females tend to spend more time in turbulent water than males , which may be due to the large difference in size between the sexes . they spend a large amount of their time basking in full sun on limestone edges , vines , and trees in or near the water . when the streams and rivers in which they live flood , barbour ' s map turtles move to where the current is weakest in the river .
field studies indicate that females take 20 or more years to reach breeding age . this fact , along with their small natural range and past over - collection for the pet trade , threatens the future of the barbour’s map turtle . reproduction has not been well - studied in the wild , but pets have produced 6 - 9 eggs in june and july .
pro . s : small adult size ( males only ; females similar in size to male res ! ) , omnivorous ( but more carnivorous than painteds ) , prominent black - tipped knobs provide a strong ‘classic’ map turtle appearance .
all of these bright colors and unique designs make map turtles fairly exotic looking despite the relative ease in acquiring one as a pet . while not often regarded as the most ideal pet turtle , they are certainly one of the more handsome looking genera of pet turtle .
barbour’s map turtles live almost all of their lives in large freshwater systems with limestone bottoms . they leave the water only to lay eggs and bask in the sun on large fallen branches and other accessible areas . they prefer deeper and faster flowing waters than other turtles in the family
level i . ) the best starter turtles : male texas map , male common map , southern painted , midland painted ( mainly males ) , stinkpot , razorback musk .
although highly aquatic , all map turtles need a dry surface on which to bask . commercial turtle docks will suffice for small specimens . cork bark , wedged or affixed via silicone to the aquarium’s sides , is a good option for adults .
hard to acquire : bog turtle . alabama red - belly ( endangered & illegal ! ) .
for outdoor enclosures , we suggest that you do not crowd your map turtles . the addition of lots of aquatic plants , especially floating varieties ( water lettuce , water hyacinth , and duckweed ) helps keep the outdoor map turtle pond healthy and keeps the oxygen level high .
an errata assessment is required to generate a revised pdf without the range map which had been included in error ; no range map was available when this assessment was originally published .
barbour’s map turtles spend nearly all of their lives in large freshwater rivers that have limestone rock on the bottom . they only come out of the water to lay eggs or bask in the sun on big fallen branches . they prefer deeper water that flows faster compared to other turtles in their
female barbour’s map turtles are very impressive , with noticeably - broad heads and shells that may approach 12 inches in length . the narrow - headed males are so much smaller – a mere 3 . 2 to 5 . 2 inches long – as to appear to be of a different species .
29 gallon aquarium – male southern painted , male texas map , male cagles map , male black - knobbed map , musk ( stinkpot , razorback , loggerhead , stripe - neck ) , larger mud turtles ( individuals , not so much species ) or pairs of muds .
in addition to the logs or rocks on the water’s surface that they can climb on , the map turtles will also want some accessories to go below the water’s surface . when map turtles go underwater , they sometimes like to seek out things like logs , thick plants , and mud to hide in . you should have lots of cozy little hiding places that your map turtle can use . make sure that they can no get stuck in the hiding places . if they get stuck they might drown .
loveridge , arthur 1946 . thomas barbour , herpetologist : 1884 - 1946 . herpetologica 3 ( 2 ) : 33 - 39 - get paper here
affordable ( ~ $ 20 - $ 50 ) : rio grande sliders ( a . k . a . ‘ornate res’ ) , common map , texas map , black - knobbed map , loggerhead musk , alligator snapper , 3 - toed box , eastern box , ornate box .
fairly uncommon in the trade : cumberland slider , river cooter , cagles map , common map ( ironic but true ) , blandings , florida chicken turtles , eastern mud , 3 - striped mud , yellow mud ( adult ) , smooth softshells , chinese softshells , eastern box turtle hatchlings .
turtle ( source , age category , species , sex if known ) must be retained by person receiving . georgia does not regulate non - native species . 4 . the following list of species native to georgia may not be held as a pet regardless of its origin or morphology : bog turtle , box turtle
male and female barbour ' s map turtles reproduce sexually , but the specific mating system is not known . males attract females by approaching them with their neck extended in an attempt to be face - to - face . the male then undertakes a courtship routine in which he touches the sides of the female’s head with the inner surfaces of his front legs for a few seconds .
pro . s : small adult size , mainly carnivorous , common , inexpensive , hibernation - capable in the southern u . s .
kirkpatrick , d . t . 1993 . an overview of the map turtles of the united states . retrieved 14 june , 2011 , from dr . david t . kirkpatrick molecular geneticist and turtle - fancier
fish can be hard for them to catch , but they will sometime eat pieces off of dead fish . at pet stores , you can usually find items like frozen shrimp or meal worms , which can be thawed and then given to your map turtle . do not feed your map turtles live meal worms . live meal worms rich in nutrients but there is a small risk that the worms might harm your turtle .
expensive ( ~ $ 75 - $ 150 ) : albino & pastel res , rio grande cooters , barbour’s maps , cagles maps , chicken turtles , stripe - neck musk , spotteds , blandings , north american wood turtles .
for plant matter , they enjoy dark leafy greens . place the greens on their basking areas above the water , as well as have them floating in the water itself . if you have an outdoor enclosure , you can plant some aquatic plants and let them grow naturally . research what kind of aquatic plants grow around the native area of your specific species of map turtle . there are other benefits to having aquatic plants in your map turtle’s outdoor enclosure , which will be covered later .
they are not as skittish as other species of map turtles , but some individuals can be . map turtles in general are sensitive to water quality , so close attention to their water quality is needed .
125 gallon aquarium – female sliders , male cooters , most female maps ( common , mississippi , ouachita ) , male barbour’s maps , blandings , north american wood , male florida softshell , female smooth & smaller female spiny softshells .
like many genera of turtle , graptemys are omnivorous . this term means they eat both plant and animal matter .
map turtles have had a devoted following in the turtle hobby for several years . these north american turtles are secretive and many species are rare in their natural habitats . they are alert baskers and active swimmers . most species are beautiful with intricate patterns . sexual dimorphism is extreme in map turtles with females reaching much larger adult sizes than males . map turtles were recently proposed for cites protection . this proposal did not proceed , but map turtles or
sawbacks
are a good species to consider for a special breeding program .
con . s : hatchlings of small species tend to be delicate . larger than a texas map . lacks the texas map’s rep . for nonchalant personality . much more expensive . carapace prone to algal overgrowth . have a rep . for being prone to health problems with sub - optimal water quality . texas native not a good candidate for hibernation .
hello & welcome to our concise guide to browsing u . s . turtles ! we cover the bulk of u . s . species by level of overall difficulty to help you pick a pet & prepare for it . this is a browsing article , not a care sheet or in - depth analysis ( for in - depth help choosing a good ‘starter’ turtle , read our article on choosing your first turtle ( we also have choosing your first land - based turtle ) ) .
shealy , r . m . 1976 . the natural history of the alabama map turtle , graptemys pulchra baur , in alabama . bull . florida st . mus . biol . sci . 21 : 47 - 111 .
ernst , c . h . and barbour , r . w . 1989 . turtles of the world . smithsonian institution press , washington d . c . - london
there are eleven species of map turtles spread throughout the united states , mostly in the southeastern river systems .
you will need to have a large aquarium tank or a large outdoor pond if you want to keep a map turtle as a pet . they need lots or room to swim around with plenty of places to hide underwater .
female barbour ' s map turtles are much larger than males . the back shell of females is 15 to 33 cm long , and the back shell of males is 9 to 14 cm long . this means that females can be 3 times bigger than males . their heads are wider too , and their lower jaw sticks out farther than their upper jaw .
large : female sliders , female western & larger eastern painted , female barbour’s maps , all cooters ( females moreso than males ) , female chicken turtles , female chinese & smooth softshells , larger male & small female spiny softshells , male florida softshells .
several species of map turtle used to be very popular in the pet trade and bred in captivity in the usa , but their popularity decreased after the enactment of the four - inch regulation in 1975 . prior to the new regulation , thousands of map turtles were bred and hatched out in captivity for the u . s pet trade . you can read more about the four - inch regulation further down of the page .
map turtles are overall not hospitable to being put into a strange environment . they are one of the harder turtle genera to care for as pets , and may not be a good choice for first time turtle owners . the difficulty in caring for them has kept them from being overly popular in the pet trade , despite their unique and beautiful shell designs .
ernst , c . h . , j . e . lovich , and r . w . barbour . 1994 . turtles of the united states and canada , smithsonian institution press .
pro . s : small adult size , mainly carnivorous , distinctive - looking .
pro . s : small adult size , mainly carnivorous , common & inexpensive .
con . s : larger than sliders ; adults deserve 125 + gallon tanks .
availability & cost : uncommon at online vendors & expo . s . ~ $
pro . s : predominantly carnivorous , attractive coloration , cold - tolerant & hibernation capable ( hail from northern u . s . around the great lakes ) .
level ii . ) second choice starter turtles : male cagles map , male chicken , male black - knobbed map , loggerhead musk , stripe - neck musk , eastern mud , mississippi mud , yellow mud , 3 - striped mud .
pro . s : small adult size ( males only ; females similar in size to male res ! ) , omnivorous ( but more carnivorous than painteds ) , more ornate coloration than a texas map .
con . s : alabama & mississippi native not a good candidate for hibernation further north ( so only in very southern u . s . ) . somewhat expensive .
tortoise and freshwater turtle specialist group 1996 . graptemys gibbonsi . 2006 iucn red list of threatened species . downloaded on 29 july 2007 .
carr and marchand 1942 . a new turtle from the chipola river , florida . proc . new england zool . club 20 : 98
the rare ringed map turtle ( g . oculifera ) is found in the pearl river in mississippi and louisiana . adult females reach 8 inches and males become sexually active at 4 inches . they feed on a variety of insects and insect larvae and the shy hatchlings enjoy daily feedings of mosquito larvae and live blackworms . female ringed map turtles lay only 3 - 4 eggs per clutch .
in addition to the lines on their shell , map turtles also have thicker lines on their face and limbs . the lines are often a bright yellow , and for many specimens ; they are even more noticeable than the “map lines” on their shell .
named after thomas barbour ( 1884 - 1946 ) , associate curator of reptiles and amphibians ( 1923 ) , and , later , director ( 1927 ) of the museum of comparative zoology at harvard .
1 . it is unlawful for any person to possess more than ten ( 10 ) native fresh - water turtles without a valid commercial turtle permit 2 . any person holding a valid commercial turtle permit may acquire live native fresh - water turtles from any source or direct trapping ,
terms & conditions | contact | privacy policy ©2007 the turtle source , inc . all rights reserved . | a deep sky studio websit e
there are several species of map turtles that are endagered and these species are in some areas illegal to keep without special permits . since some map turtles are so small , the four - inch law can make it harder to find a good pet specimen .
sexual dimorphism is present in barbour ' s map turtles . females are much larger than males . females have a carapace that is 15 to 33 cm long at sexual maturity , whereas mature males have a 9 to 14 cm carapace . therefore , females can be up to three times the size of males . females also have much wider heads than males , along with a lower jaw that extends past the upper jaw .
con . s : large females deserve 125 + gallon tanks . rep . for skittishness .
kirkpatrick , david 1993 . map turtles of the united states . reptile & amphibian magazine ( november / december ) : 7 - 17
black - knobbed map turtles ( g . nigrinoda ) are found in the tombigbee and black warrior river systems in alabama and misssissippi .
map turtles are omnivores . in captivity , the majority of their captive diet consists of floating aquatic turtle food and a variety of aquatic plants . typically , hatchlings and young map turtles feed on more plant matter than adults . physically , adults develop large , muscular jaws in response to a natural diet of hard - shelled snails and crayfish . they also eat a wide variety of insects . freeze - dried shrimp and krill are a great treat for map turtles . these can be bought in most pet stores that offer tropical fish food and supplies .
distribution and habitat : barbour ' s map turtles can be found in the gulf coastal plain in the apalachicola and choctawhatchee river systems . this limited range includes parts of southeast alabama , southwest georgia , and the florida panhandle . the chattahoochee , flint , and chipola rivers in which these turtles reside are clear flowing with limestone rock and cobble bottoms . they are also rich in mollusks and contain many fallen trees and exposed rocks for basking .
barbour ' s map turtles are like many reptiles in that there is little parental investment . the male courts the female to mate with her . once his sperm is deposited he no longer invests time or energy in the young . the female digs a nest in which to deposit eggs and covers it with dirt . once the nesting is complete , the female leaves the eggs and does not invest further time or energy in the offspring .
know that aquatic turtles do not like to be held or cuddled . reptiles in general are not affectionate animals , but it is best that you do not pick up your map turtle at all unless you have to . if you do handle your map turtle , wash your hands thoroughly afterward . aquatic turtles can sometimes spread things like salmonella . this is not too big of a danger so long as you use basic care techniques ( such as washing your hands after handling ) and a little common sense . nut it is still a risk you should be aware of .
availability & cost : uncommon in the pet trade but often common in the live turtle food industry ( which you fund with your purchase ! ) .
description : very small mildly domed black turtle with large orange or yellow patches behind the eyes . size : 3 - 4 . 5
scl .
a good rule of thumb to determine if an outdoor pond is an option is to research the species of map turtle you own , and see if any live in the wild in your area . if they do live in the wild in your area , then an outdoor pond may have temperatures that are naturally hospitable to them . it is however important to remember that a small pond will get colder in the winter and hotter in the summer than a larger body of water so your pond is not necessarily a good map turtle habitat even if they live in your area .
availability & cost : uncommon at online vendors & expo . s . ~ $ for hatchlings .
choose the plan that ' s right for you . digital access or digital and print delivery .
the lifespan of map turtles is not very long compared to other turtles . many turtle species can live over a hundred years . american box turtles will as an example live 75 years or more . map turtles tend to only live up to twenty - five years in the wild , and their life expectancy in captivity is lower . so while they make beautiful pets , they do not live long by the standards of a reptile .
many species of turtle and tortoise are endangered in the wild . always check the rules regarding keeping turtles and tortoises as pets that apply to your area .
the cuatro ciénegas slider ( trachemys taylori ) [ 2 ] [ 3 ] is a species of turtle belonging to the genus trachemys of the family emydidae .
barbour ' s map turtle eggs have a shell that holds the developing turtle and a yolk sac . the baby turtles take 58 days to come out of the eggs . they look just like miniature adults when they ' re born , except that their colors aren ' t as bright . their back shell is 37 mm long on average and weighs around 10 . 7 g . whether the turtle is male or female depends on how warm the eggs are before they hatch . if the eggs are less than 25 degrees celsius , only males are born . if the eggs are warmer than 30 degrees celsius , only females are born . males are able to have their own young when they are 2 to 4 years old , but females can ' t until they are 15 to 20 years old . this explains why females are bigger than males . females also have bigger spaces in their shells that allow them to get bigger .
55 gallon aquarium – female southern painted , male midland painted , male common , mississippi or ouachita map , spotted turtles , pacific pond turtles .
alabama map turtles ( g . pulchra ) are found from the yellow river in alabama and florida to the pearl river in mississippi and louisiana .
1 . it is unlawful for any person to possess more than ten ( 10 ) native fresh - water turtles without a valid commercial turtle permit . nothing in
map turtles are freshwater turtles belonging to the genus graptemys in the family emydidae . they are native to north america , where they are found throughout the eastern half of the usa and northward into southern canada . in addition to being called map turtles , they are also known as sawback turtles .
availability & cost : uncommon at online vendors & expo . s . ~ $ 30 for hatchlings . tom c . knows them to be widely abundant in texas , yet hardly anyone shows interest in breeding them ! i ' ve seen turtle pimp offer these .
pro . s : small adult size ( males < females ) , omnivorous , usually peaceful , common & inexpensive , can hibernate in the southern u . s . fairly personable / interactive with humans .
availability & cost : uncommon at online vendors & expo . s . ~ $ 20 for hatchlings .
pro . s : small adult size , mainly carnivorous , ornate & distinctive - looking , inexpensive .
availability & cost : uncommon at online vendors & expo . s . ~ $ 10 for hatchlings .
availability & cost : uncommon at online vendors & expo . s . ~ $ 65 for hatchlings .
con . s : larger than southern or midland painteds . large females deserve 125 + gallon tanks .
availability & cost : uncommon at online vendors & expo . s . ~ $ 15 for hatchlings .
availability & cost : common at online vendors & expo . s . ~ $ 15 for hatchlings .
availability & cost : uncommon at online vendors & expo . s . ~ $ 75 for hatchlings .
pro . s : omnivorous . distinctive & unusual . adult size : up to 8
scl .
you will also need areas on top of their body of water that they can climb onto , such as logs or mounds made of rock or dirt . map turtles like to come out of the water sometimes and bask in the sun . reptiles cannot regulate their own body heat so access to an external heat source is crucial . if your map turtle is being kept in a tank , you can have a heat lamp set up above their basking areas .
goldfish should be used sparingly , if at all , as a steady goldfish diet has been linked to kidney and liver disorders in other turtle species . a high quality commercial turtle chow can comprise up to 30 % of the diet . a cuttlebone should be available to supplement the calcium provided by whole fishes and similar foods .
adult females of most species of map turtles can reach 7 inches and adult males are considerably smaller , with most only reaching 5 - 6 inches .
dampier , l . 1998 . map turtles : an american specialty . reptile hobbyist , vol . 4 , no . 3 , 36 - 44 .
description : small basking turtle , quite ornate coloration , care like sliders . sizes : males 2 . 75 – 5” , females 4” to 7 15 / 16” .
availability & cost : very common at online vendors & expo . s . ~ $ 15 for hatchlings .
availability & cost : fairly common at online vendors & expo . s . ~ $ 15 for hatchlings .
pro . s : small adult size , mainly carnivorous , most ornate of the u . s . mud / musk , inexpensive . reputedly have ‘stinkpot - like’ personalities ( less shy than young mississippi muds ) .
availability & cost : at online vendors & expo . s . ~ $ 10 - 15 for hatchlings .
seidel , michael e . & carl h . ernst 2017 . a systematic review of the turtle family emydidae vertebrate zoology 67 ( 1 ) : 1–122 - get paper here
you have opened an old version of the turtle urltoken website . to place an order , or to see our available turtles and tortoises please click here - thank you .
map turtles get their name from their appearance . their carapace ( the top / dome portion of their shell ) has designs on it that resembles those seen on some maps . specifically , it has been noted that the lines on their shells look like waterways on a map . these lines are often a yellow or orange color , with darker colors in between them such as greens and browns . the lines on the map turtles shell can fade some as they age .
barbour ' s map turtles have dark brown or black skin with light yellow or green markings . they have broad heads with special patterns in yellow on the top of their head and behind their eyes . a light - colored bar on their chin goes around the curve of their jaw . the top of their neck , back legs , and tail have stripes . the shell on top of their back is like a big olive green dome with dark spines . the second and third spine are the biggest , but they wear down as the turtle gets older . the part of the shell that covers their belly is yellow and there is a black border at the edge of each section .
con . s : a little larger than s . painted . less ornate plastron than western painted . carapace color varies – green to black ( so your hatchling may not look like the one in a photo ) .
con . s : hatchling musk somewhat delicate . huge heads aren’t to everyone’s taste . musk turtles generally are regarded as prone to aggression toward their own kind & ‘look - a - likes . ’ less likely to be personable than sliders . southeastern u . s . native shouldn’t be hibernated outside its native range or similar conditions .
they are aquatic turtles , and while they can spend time on land ; most of their time is spent in the water . map turtles do not live in salt water ; they only live in freshwater environment such as ponds and rivers . they tend to prefer river systems with flowing water . ideal map turtle environments contain lots of underwater plant matter that they can eat , as well as rocks and logs that they can rest on when heating themselves in the sunlight . commonly referred to as basking .
reproduction in which eggs are released by the female ; development of offspring occurs outside the mother ' s body .
availability & cost : uncommon at online vendors & expo . s . ~ $ 20 - 25 for hatchlings .
availability & cost : common at online vendors & expo . s . ~ $ 10 - 15 for hatchlings .
internet have made buying map turtles directly from private breeders a lot easier and it is today often possible to find small turtles without ever having to leave your home .
availability & cost : fairly common at online vendors & expo . s . ~ $ 5 - 10 for hatchlings .
availability & cost : very common at online vendors & expo . s . ~ $ 10 - 15 for hatchlings .
con . s : larger than sliders ; adults deserve 125 + gallon tanks . florida native so hibernation not advised .
pro . s : predominantly carnivorous , males smaller than sliders , usually peaceful , fairly inexpensive , hibernation - capable .
availability & cost : fairly common at online vendors & expo . s . ~ $ 125 - 130 for hatchlings .
there are several drawbacks to map turtles as pets , such as being a challenge to care for in captivity when compared to some other turtles such as red eared sliders .
the type of food you give them will vary depending on which gender of map turtle you have . this is because the females are much larger than the males , and so their superior jaws can consume larger prey . the females can consume prey as large as clams and snails , whereas males have to be fed things like tiny crustaceans and aquatic insects .
availability & cost : one of only 2 non - marine federally endangered turtle species in the united states . the upshot is , can only be had wild - caught & then illegally .
ennen , joshua r . ; jeffrey e . lovich , brian r . kreiser , w . selman , carl p . qualls 2010 . genetic and morphological variation between populations of the pascagoula map turtle ( graptemys gibbonsi ) in the pearl and pascagoula rivers with description of a new species . chelonian conservation and biology . 9 ( 1 ) : 98–113 - get paper here
how large your tank or pond should be depends on how many map turtles you want to keep and what species of map turtles you want to keep . they are not particularly aggressive animals and are social enough that you can keep them together . however , there can be exceptions to this if there is not enough space and food to go around .
pro . s : omnivorous ( but more carnivorous than eastern box ) . smallest north american box turtle . older juveniles & adults fairly affable / interactive with humans & shell provides good protection . eager feeders . can be low - maintenance in year - round outdoor enclosures in compatible climates . fairly easy to find .
level iii . ) medium - level turtles : sliders ( north american ) , cooters ( all ) , eastern & western painted , most maps ( including mississippi , ouachita , false , female common , barbour’s , female texas & cagles , etc… ) , female chicken turtles , chinese softshells , male spiny & smooth softshells , spotted turtles , florida mud , eastern & 3 - toed box turtles .
pro . s : small adult size , mainly carnivorous , look like they’re smiling . hibernate in parts of their range .
pro . s : predominantly carnivorous , males smaller than sliders , usually peaceful , common & inexpensive , hibernation - capable .
these large , active turtles require spacious homes . while a 55 gallon aquarium might suit a small male , females need tanks of 125 – 200 gallon capacity , or commercial turtle tubs and ponds .
the sale , holding for sale , and distribution of live turtles and viable turtle eggs not in connection with a business . “ , sec . 1240 . 62 ( d ) ( 2 ) .
removing your turtles to an easily - cleaned container for feeding will lessen the filter’s workload and help to keep the water clean .
con . s : hatchlings reputedly delicate . plastron plain compared to western & midland painteds . not appropriate for northern winter hibernation .
con . s : larger than sliders ; adults deserve 125 + gallon tanks . small southern alabama range so hibernation not recommended .
pro . s : predominantly carnivorous , males smaller than sliders , usually peaceful , fairly common & inexpensive , hibernation - capable .
bartlett , r . d . 1998 . notes from the field : notes on ringed and other map turtles . reptiles , vol . 6 , no . 5 , 76 - 81 .
availability & cost : uncommon at online vendors & expo . s but can be found . ~ $ 50 - 75 for hatchlings .
description : medium basking turtle , reticulated carapace , more pointed face than sliders , long - neck , have ‘strike & suck’ maneuver to catch prey . size : males 4 – 7” , females up to 10” .
availability & cost : somewhat uncommon at online vendors ; may appear at larger expo . s . ~ $ 25 - 40 for hatchlings .
availability & cost : fairly common to uncommon at online vendors ; may appear at larger expo . s . ~ $ 130 for hatchlings .
availability & cost : fairly common to uncommon at online vendors ; may appear at larger expo . s . ~ $ 40 for hatchlings .
availability & cost : fairly easy to find online & at expo . s but expensive . cost ~ $ 60 - 125 for hatchlings .
6 . ) most map turtles , including females . map turtles has a group have a reputation for being unusually sensitive to poor water quality ( cagles & black - knobbed have specifically been mentioned ; tom c . thinks common maps may be more resistant ) & skittishness ( mississippi maps have specifically been mentioned ; texas maps may be an exception ) . in all maps the female is drastically larger than the male .
con . s : larger than southern or midland painteds ; bland plastron unlike midland & western painteds ; large females deserve 75 + gallon tanks .
pro . s : omnivorous & can feed on land or in water . very small & quite attractive . northeastern native so hibernation - capable .
wading pools are often easier to manage than aquariums . koi ponds sometimes contain shelves meant to hold plants ; these work well as turtle basking areas . outdoor housing is ideal , assuming that raccoons and other predators can be excluded .
description : small basking turtle , prominent black - tipped dorsal carapace spine knobs , care like sliders . there are 2 subspecies but native range very small . sizes : males 3 – 4” , females 6 – 8 . 5” .
typically , hatchling & young map turtles that are still growing will have a more carnivorous diet than their adult counterparts . this is because young turtles are still growing , and need the extra protein in their diet .
team wild , an elite squadron of science superheroes , needs your help ! your mission : protect and conserve the planet’s species and habitats from destruction .
con . s : larger than sliders ; adults deserve 125 + gallon tanks . uncommon & expensive . largely a texas native so hibernation not advised .
except as otherwise provided in this section , viable turtle eggs and live turtles with a carapace length of less than 4 inches shall not be sold , held for sale , or offered for any other type of commercial or public distribution . ”
description : medium - sized terrestrial turtle which likes to soak . steeply domed carapace , single - hinged plastron , can close the shell tightly , males & females have different coloration / patterning . size : 4 . 5 – 5 . ”
description : medium - sized terrestrial turtle which likes to soak . steeply domed carapace , single - hinged plastron , can close the shell tightly , fairly colorful carapace & head . size : ornate 4 – 5” ( up to 6 ) .
description : small basking turtle , fairly hardy adults , care like sliders . olive brown carapace with intricate designs ( or algae covered ! ) . sizes : males 2 . 75 – 4 . 5” , females 4 – 8 3 / 8” .
availability & cost : very common at online vendors & expo . s . ~ $ 5 - 10 for hatchlings ( color morphs much more expensive ) .
con . s : less prominent keeling along dorsal spine than many maps . carapace prone to algal overgrowth . somewhat hard to find in the pet trade .
the guidelines are part of the state’s imperiled species management plan , which was passed in november 2016 and involved status changes that went into effect in february .
pro . s : small adult size , mainly carnivorous , reduced plastron suggests better adapted to a more aquatic existence ( peterson’s field guide to repiles & amphibians of eastern / central north america page 155 states they’re more aquatic than eastern muds ) . males have larger heads that may rival male loggerhead musk in size .
description : small basking turtle , fairly hardy adults , care like sliders . black carapace , scutes have some light trip , red dorsal red stripe , plain plastron . size : males 3 . 5 – 5” ; females 5 . 5 – 7” .
description : large basking turtle , reticulated carapace , more pointed face than sliders , long - neck , have ‘strike & suck’ maneuver to catch prey . female florida subspecies can be quite thick . size : males 4 - 7” females up to 10” .
description : small bottom - walker , fairly hardy adults , olive brown coloration , most reduced plastron of any u . s . mud turtle , care not well - known but at least some shallow water areas & at least a small land area recommended . they’re a subspecies of the eastern mud , which spends a lot of land , making this turtles’ needs hard to call . size : 4 – 5” .
florida fish and wildlife conservation commission • farris bryant building 620 s . meridian st . • tallahassee , fl 32399 - 1600 • ( 850 ) 488 - 4676
availability & cost : uncommon at online vendors & expo . s . protected in florida , where many online vendors are located . ~ $ 40 for hatchlings .
con . s : hatchlings somewhat delicate . expensive & hard to find . musk turtles generally are regarded as prone to aggression toward their own kind & ‘look - a - likes . ’ less likely to be personable than sliders . southeastern u . s . native shouldn’t be hibernated outside its native range or similar conditions .


in zoology , a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants .

nectar as a food source presents a number of benefits as well as challenges .

it is essentially a solution of ( as much as 80 % ) the simple sugars sucrose , glucose and fructose , which are easily ingested and digested , representing a rich and efficient source of nutrition .

this solution is often diluted either by the plant that produces it or by rain falling on a flower and many nectarivores possess adaptations to effectively rid themselves of any excess water ingested this way .

however , nectar is an incomplete source of nutrition .

while it does contain proteins and amino acids , these are found in low quantities , and it is severely deficient in minerals and vitamins .

very few organisms consume nectar exclusively over their whole life cycle , either supplementing it with other sources , particularly insects ( thus overlapping with insectivores ) or only consuming it exclusively for a set period .

many species are nectar robbers or nectar thieves , performing no pollination services to a plant while still consuming nectar .

nectar is produced by flowering plants to attract pollinators to visit the flowers and transport pollen between them .

flowers often have specialized structures that make the nectar accessible only for animals possessing appropriate morphological structures , and there are numerous examples of coevolution between nectarivores and the flowers they pollinate .

for example , hummingbirds and hawkmoths have long narrow beaks that can reach nectar at the bottom of long tubular flowers .

bats , meanwhile , visit open flowers where the nectar is not as deeply hidden .

nectarivore

nitrogen requirements of an old world nectarivore , the orange - tufted sunbird nectarinia osea .
nitrogen requirements of an old world nectarivore , the orange - tufted sunbird nectarinia osea . - pubmed - ncbi
nectarivore - ( from the greek work nektar , the drink of the gods ) a creature deriving its energy from the sugar rich nectar of flowering plants .
…that feed on nectar ( nectarivore s ) and have life spans longer than the flowering time of one plant species have mutualistic relationships with a succession of pollinating species in order to survive .
during the same time that a [ pis ] m [ ellifera ] adansonii encounters on flowers were registered , we noted the type of floral products collected by this bee . this parameter was measured to determine if a . m . adansonii is strictly a pollinivore , nectarivore or pollinivore and nectarivore . this could give us an idea of its implication as a cross - pollinator of g [ ossypium ] hirsutum .
citation : welch kc jr , allalou a , sehgal p , cheng j , ashok a ( 2013 ) glucose transporter expression in an avian nectarivore : the ruby - throated hummingbird ( archilochus colubris ) . plos one 8 ( 10 ) : e77003 . urltoken
colour me in . it ' s nectar of a new sort . nectarivore certifed organic ipa , a big hoppy , colourful cocktail of organic new zealand hops , pineapple sage and hibiscus . there ' s oodles of colour inside , but we ' ve left the outside to you . stay in the lines , or not - it ' s up to you . happy 25th birthday common sense organics .
another possible route for elimination of surplus water is through evaporation . evaporative water loss ( ewl ) of anna ' s hummingbird is high because of its high mass - specific metabolic rate , but high excretory losses mean that ewl still represents a far smaller proportion of daily water loss compared with other birds and mammals ( powers , 1992 ) . estimates calculated from the difference between water gain and cloacal fluid output have also yielded high ewl values for sunbirds and honeyeaters ( collins , 1981 ; fleming and nicolson , 2003 ; lotz and nicolson , 1999 ) . nothing is known of the partitioning of evaporation between cutaneous and respiratory routes , but cutaneous ewl is influenced by hydration state in other birds ( williams et al . , 2012 ) . unfortunately , the high excretory output of avian nectarivores complicates the direct measurement of ewl , and the pharmacokinetic method has proved unreliable for its estimation ( purchase et al . , 2013b ) . further research in this area is required to determine the role of evaporation in osmoregulation for the three avian nectarivore lineages .
sugar preferences and sucrase activity in nectar - feeding birds . ( a ) concentration - dependent sugar preferences of red wattlebirds , anthochaera carunculata ( fleming et al . , 2008 ) . birds were offered pairs of sucrose and hexose ( fructose + glucose ) solutions of varying concentrations from 0 . 075 to 2 mol l −1 sucrose equivalents ( se ) . diets where birds did not achieve energy balance are indicated with increasingly lighter shaded symbols . values are means ± 1 s . d . index of sugar preference ( i . e . hexose ingested as a proportion of total sugar ingested ) . asterisks indicate significant preferences for either hexose or sucrose diets ( * p < 0 . 05 ) and different letters indicate diets that were significantly different from each other in terms of the index of sugar preference ( anova and post hoc analysis ) . ( b ) relationship between degree of hexose preference ( i . e . minimum concentration where no sugar preference was indicated ) and standardized intestinal sucrase activity in 11 nectarivore species ( napier et al . , 2013 ) . data are average values for each species . white symbols denote diet generalists and grey symbols nectar specialists .
whole - kidney glomerular filtration rate ( gfr ; a measure of the rate at which the kidneys filter the plasma ) is much more responsive to hydration state in birds than in mammals , decreasing with dehydration or salt loading and increasing with water loading ( goldstein and skadhauge , 2000 ) . studies carried out in a range of bird species indicate that this is due to release of arginine vasotocin ( avt ) , which acts mainly on gfr , while having a relatively modest effect on the water permeability of the collecting ducts ( goldstein , 2006 ; nishimura and fan , 2003 ) . the reduction of gfr by avt occurs through a decrease in filtration by reptilian - type nephrons , with mammalian - type nephrons being less affected ( goldstein and skadhauge , 2000 ) . in nectarivores , plasma avt concentration increases with increasing sugar concentration , presumably reflecting a hormonal response to increased plasma osmotic concentration ( gray et al . , 2004 ) . surprisingly , in view of the high variation in water intake , gfr does not vary with water loading for the three avian nectarivore lineages ( goldstein and bradshaw , 1998 ; hartman bakken and sabat , 2006 ; purchase et al . , 2013b ) , although gfr is greatly reduced at night ( see below ) .
high water fluxes are a problem for salt conservation , and avian nectarivores are very efficient at minimizing electrolyte losses in the cloacal fluid : for example , whitebellied sunbirds feeding on 0 . 25 mol l −1 sucrose solutions void cloacal fluid with an osmolality of only 6 mosmol kg −1 ( fleming and nicolson , 2003 ) . despite similar abilities to produce copious volumes of dilute excreta across the three nectarivore lineages , the birds handle dilute diets differently . extremely dilute , sucrose diets devoid of electrolytes cause hummingbirds to stop feeding and go into torpor , while honeyeaters and sunbirds suffer decreased plasma sodium levels and are unable to maintain energy balance ( fleming et al . , 2004c ; goldstein and bradshaw , 1998 ; lotz and martínez del rio , 2004 ) . nectarivores thus appear to be constrained in their intake of dilute diets due to hyponatremia , i . e . low plasma sodium concentration ( fleming and nicolson , 2003 ) , and the addition of even small amounts of sodium ( 5–10 mmol l −1 ) to very dilute sucrose diets results in a marked decrease in plasma aldosterone concentration ( the active principle of the renin–angiotensin–aldosterone system , stimulating renal reabsorption of sodium ) ( fleming et al . , 2004a ) and enables whitebellied sunbirds and new holland honeyeaters to increase consumption , up to an extraordinary eight times their body mass daily ( purchase et al . , 2010 ) .
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parallel adaptations to nectarivory in parrots , key innovations and the diversification of the loriinae . - pubmed - ncbi
warning : the ncbi web site requires javascript to function . more . . .
parallel adaptations to nectarivory in parrots , key innovations and the diversification of the loriinae .
schweizer m 1 , güntert m 1 , seehausen o 2 , leuenberger c 3 , hertwig st 1 .
naturhistorisches museum der burgergemeinde bern bernastrasse 15 , ch 3005 , bern , switzerland .
aquatic ecology and macroevolution , institute of ecology & evolution , university of bern baltzerstrasse 6 , ch 3012 , bern , switzerland ; fish ecology and evolution , eawag seestrasse 79 , ch 6047 , kastanienbaum , switzerland .
department of quantitative economics , university of fribourg boulevard de pérolles 90 , ch 1700 , fribourg , switzerland .
specialization to nectarivory is associated with radiations within different bird groups , including parrots . one of them , the australasian lories , were shown to be unexpectedly species rich . their shift to nectarivory may have created an ecological opportunity promoting species proliferation . several morphological specializations of the feeding tract to nectarivory have been described for parrots . however , they have never been assessed in a quantitative framework considering phylogenetic nonindependence . using a phylogenetic comparative approach with broad taxon sampling and 15 continuous characters of the digestive tract , we demonstrate that nectarivorous parrots differ in several traits from the remaining parrots . these trait - changes indicate phenotype - environment correlations and parallel evolution , and may reflect adaptations to feed effectively on nectar . moreover , the diet shift was associated with significant trait shifts at the base of the radiation of the lories , as shown by an alternative statistical approach . their diet shift might be considered as an evolutionary key innovation which promoted significant non - adaptive lineage diversification through allopatric partitioning of the same new niche . the lack of increased rates of cladogenesis in other nectarivorous parrots indicates that evolutionary innovations need not be associated one - to - one with diversification events .
pmid : 25165525 pmcid : pmc4130445 doi : 10 . 1002 / ece3 . 1131
longitudinal section through the epithelium at the border ( arrow ) between the esophagus ( right ) and the proventriculus ( left ) of psittrichas fulgidus . the compound glands ( cg ) of the proventriculus can be clearly distinguished from the mucous glands ( mg ) of the lower part of the esophagus .
schematic illustration of a caudal view and a transverse section along the median plane between the tendineal centers ( right ) of the gizzard . the measurements taken in this study are indicated . modified from ziswiler ( ) .
schematic illustration of a transverse section through the gizzards along the median plane between the tendineal centres of a nectarivorous ( vini australis , left ) and a granivorous parrot ( neophema chrysostoma , right ) .
best - scoring maximum likelihood tree including bootstrap values above 70 % indicated at nodes . this tree was used for the formulation of the hypothesis of the variance - covariance matrix of the error terms in the regression analyses . nectarivorous species are shown in red .
natural - log transformed values of the different independent variables against natural - log transformed body masses including the regression lines of the best - fitting model . for all these traits , the data were best explained by an allometric relationship between the dependent and independent variables .
natural - log transformed values of the different independent variables against natural - log transformed body masses including the regression lines of the best - fitting models . for all these traits , a model including the nectarivorous diet as a covariate with different intercepts but the same slope was considered as the best - fitting model .
out of the 40 . 000 or more species of spiders found up to date , every single one of them is a predator , capturing their prey using a complicated web , hunting them directly , or using other creative methods ; all except one , that is . bagheera kiplingi ( odd choice for a veggie spider ) is the first species that primarily feasts on something else than meat .
the type of plants it enjoys is called beltian bodies , and it basically represents leaf - tip structures that are produced by acacia . what’s really interesting is that another animal that fancies the same food is the ant . some ants have an almost symbiotic relationship with the acacia shrubs , living in the hollow spines and eating an amount that also allows the acacia to thrive , and protecting the plants from other invaders . this relationship has been studied and described in numerous studies .
“this is really the first spider known to specifically ‘hunt’ plants ; it is also the first known to go after plants as a primary food source , ” said christopher meehan of villanova university , who took notice of the spiders during a field course in mexico .
even more , this species of spider is the first known to eat solid vegetative food at all . they do occasionally prey on small invertebrates , but in an overwhelming proportion , their food is vegetal .
“i’ve done the math several times , and even the most conservative estimates point to near - total vegetarianism , ” meehan said . “almost all of the prey that the spiders do eat are acacia - defending ant larvae . ”
“spiders aren’t really thought to be capable of eating solid food at all , ” meehan said . spiders digest their prey externally , he explained , and any matter bigger than about one micrometer gets filtered out of the vital juices in the spider’s pharynx . beltian bodies , however , are 80 percent structural fiber , and quite large by spider standards . “the acacia spiders consume these nutrient - enriched—but not particularly nutrient - rich—’vegetables’ completely , often in less than five minutes . ”
but eating the food of an ant colony… that’s definitely not something you should be eager to do , so how does the spider get away with it ? ? well , according to meehan , they have what can only be called “sheer wit” .
“jumping spiders in general possess incredibly advanced sensory - cognitive skills and eight - legged agility , and bagheera is no exception , ” he said . “individuals employ diverse , situation - specific strategies to evade ants , and the ants simply cannot catch them . ”
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avenues of water gain and loss in bees are examined here at two levels of organisation : the individual and the colony . compared with the majority of terrestrial insects , bees have a high water turnover . this is due to their nectar diet and , in larger species , substantial metabolic water production during flight , counteracted by high evaporative and excretory losses . water fluxes at the colony level can also be very high . when incoming nectar is dilute , honeybees need to remove large volumes of water by evaporation . on the other hand , water is not stored in the nest and must be collected for evaporative cooling and for feeding the brood . water regulation has many similarities at individual and colony levels . in particular , manipulation of nectar or water on the tongue is extensively used by bees to increase evaporation for either food - concentrating or cooling purposes .
bees are not normally model insects for studying water balance . bee physiology is characterised by endothermy in even small species ( stone and willmer , 1989 ) and is complicated by the social context . bees show the full spectrum of sociality : although most are solitary it is the social bumblebees and honeybees whose physiology and behaviour are most familiar to us ( willmer and stone , 2004 ) . in addition , the sophisticated thermal physiology of bees has received much more attention ( e . g . heinrich , 1985 ; kovac et al . , 2007 ) than their water regulation . here i briefly examine the water balance physiology of bees , considering the usual avenues of water gain and loss , at two levels of organisation : the individual and the colony , sometimes termed a ` superorganism ' ( moritz and southwick , 1992 ) . it is accepted that social homeostasis can be explained by the coordinated activity of bees as individuals , responding to their internal or external environment , without the need to invoke centralised control ( jones and oldroyd , 2007 ; seeley , 1995 ) .
water fluxes of honeybees can be very high at the colony level . for example , seeley estimated average annual requirements of 120 kg of nectar , 20 kg of pollen and 25 litres of water for a single wild colony ( seeley , 1995 ) . this applies to honeybees in cold temperate conditions , and the estimate for nectar includes substantial energy stores required for over - wintering . the seasonal cycles of african honeybees are limited by rainfall , not temperature , and better foraging weather means that in comparison massive honey stores are not needed ( hepburn and radloff , 1998 ) .
while male bees of most species take care of their own energetic needs , all female bees forage far beyond their individual needs , collecting pollen and nectar as provisions for the offspring they raise ; therefore activity patterns of the sexes may be very different ( willmer and stone , 2004 ) . where comparisons have been made , male xylocopa capitata and anthophora plumipes carry much smaller crop loads than do females ( louw and nicolson , 1983 ; stone , 1995 ) . the impermeable crop expands greatly for storage and transport of nectar and protects the haemolymph from osmotic shock . apis mellifera workers can carry close to their body mass in nectar , although crop loads tend to be much smaller ( schmid - hempel et al . , 1985 ) and are positively correlated with the nectar concentration ( hunt et al . , 1995 ) . this suggests that under natural conditions honeybees might carry less than during experiments in which they are fed concentrated sugar syrup ( e . g . park , 1932 ; waller , 1972 ) . their feeding system is designed to retain nectar in the crop for as long as possible . sugar leaves the crop at a rate dependent on the metabolic rate of the individual , but the fluid - emptying rate ( and the rate of rectal filling ) are inversely proportional to nectar concentration ( roces and blatt , 1999 ) .
female allodapula variegata concentrating the dilute ( 14 % ) nectar of aloe arborescens by evaporation . the regurgitated droplet , held under the tongue , is repeatedly sucked in and out and may be very large in relation to the size of the bee ( body length 7 mm ) . photo , michael ellis .
fresh pollen is relatively dehydrated after exposure at anthesis , but its water content increases after collection by bees due to the addition of nectar and glandular secretions ( human and nicolson , 2006 ) . the larval diets of bees vary greatly in water content ( roubik , 1989 ) . the water content of royal jelly is around 67 % ( wongchai and ratanavalachai , 2002 ) , but the larval food of stingless bees contains less water , a thicker consistency being necessary for larvae floating on top of mass provisions ( hartfelder and engels , 1989 ) . large carpenter bees provision their nests with semi - solid masses of pollen combined with nectar , giving a final water content of only 20 % in the provisions of x . capitata ( louw and nicolson , 1983 ) . in xylocopa mordax , nectar is pre - concentrated on the tongue for this purpose ( corbet and willmer , 1980 ) .
honeybees prefer sugar concentrations of 30–50 % ( sugar concentrations here are given as % w / w as in refractometer measurements ) under experimental conditions ( waller , 1972 ) , but in practice they collect from a much wider range of nectars . seeley measured 15–65 % in nectar loads being brought into a single colony ( seeley , 1986 ) , and hunt and colleagues recorded a similar range of concentrations in incoming loads ( hunt et al . , 1995 ) . the choice of nectar concentration depends on the ecological context , i . e . on the other food sources available at the time . this has long been a complicating factor in experimental studies of honeybee foraging behaviour . for example , lindauer found that the threshold sucrose concentration for eliciting recruitment behaviour declined from 55 % to 4 % as the german summer progressed ( lindauer , 1948 ) . empirical measurements of energy intake rate in bees show peak values at sucrose concentrations around 60 % in bumblebees , stingless bees and honeybees ( harder , 1986 ; roubik and buchmann , 1984 ) . note that for orchid bees ( euglossini ) , which use suction feeding rather than a lapping mechanism , optimal concentrations are lower and more dilute nectars are collected ( borrell , 2004 ) .
communal food storage requires that the osmolality of honey is high enough to inhibit microbial growth ( pusey , 1999 ) . in honeybees this is achieved first by hydrolysis of nectar sucrose to glucose and fructose , through the addition of hypopharyngeal gland enzymes , and then through evaporative processing by food - handling bees to reach a concentration of about 82 % . these bees evaporate nectar on their tongues before placing droplets in open cells for further evaporation , accelerated by fanning ( park , 1925 ) . among stingless bees , workers drink water condensed in the nest during honey ripening and regurgitate it outside the entrance ( roubik , 2006 ) . their ripened honey is around 70 % in concentration and tends to ferment ( cortopassi - laurino et al . , 2006 ; roubik , 2006 ) . note that uncapped honey is hygroscopic and absorbs water , so can be both a sink and source of water in the nest .
trophallaxis is the regurgitation of the crop contents of a donor bee for ingestion by receiver bees . extremely rapid distribution of incoming nectar was demonstrated by nixon and ribbands , who fed radiolabelled food to six foragers and were able to detect the label in 62 % of all foragers after only 4 h and in all large larvae in unsealed cells after 48 h ( nixon and ribbands , 1952 ) . trophallactic interactions ensure that homeostasis is achieved in the ` collective stomach ' of all workers , which is a nectar reserve for the colony ( schmickl and crailsheim , 2004 ) . similarly , colonies preparing to swarm store concentrated food in their crops , comprising 20–30 % of the mass of individuals and of the swarm ( combs , 1972 ) . in addition to its nutritional significance , liquid transfer between adults is a means of exchange of information about the quality and quantity of food reserves in the colony ( crailsheim , 1998 ) .
it is not clear whether solitary bees drink water for their own needs , as distinct from seeking dilute nectar . large aggregations of bees of various genera can be seen foraging at wet soil substrates in the tropics , then regurgitating and reimbibing fluid , and this may be a means of obtaining salts ( roubik , 1989 ) . although bumblebees are not expected to drink , marked bombus terrestris were observed drinking repeatedly from a water trough during warm conditions ( ferry and corbet , 1996 ) : it is unlikely that individual bumblebees would have a water deficit so this was probably for the benefit of the colony . when groups of 100 honeybees are confined in cages and provided with 67 % sugar , they drink about 10 μl of water daily at t a of 35°c and 40°c ( free and spencer - booth , 1958 ) .
honeybee colonies collect water for two reasons , related to different types of weather : for cooling of the brood area by evaporation on hot days , and for feeding the larval brood when foraging is limited on cool days ( lindauer , 1955 ; seeley , 1995 ) . the classic studies of lindauer showed how bees regulate the hive temperature in hot conditions ( lindauer , 1955 ) . water is collected by water foragers , then distributed around the hive and in cells containing eggs and larvae ; fanning accelerates its evaporation , as does regurgitation and evaporation on the tongue ( lindauer , 1955 ) . visscher and colleagues measured mean water loads of 44 mg in honeybees collecting water under desert conditions ( visscher et al . , 1996 ) . paper wasps and hornets also use water for cooling their nests , but the highly social stingless bees do not ( jones and oldroyd , 2007 ; roubik , 2006 ) .
the second need for water – for consumption by nurse bees when feeding the brood – is an aspect of water use by honeybees that tends to be underestimated ( johansson and johansson , 1978 ) . nurse bees feed young larvae a secretion from their hypopharyngeal glands ; for worker larvae after the third day this jelly is supplemented with honey and pollen ( crailsheim , 1998 ) . as already mentioned , the water content of royal jelly is high , so nurse bees have a great need for water when brood rearing is intensive ; this water cannot always be obtained from nectar .
the regulation of water collection in honeybees is discussed in detail by seeley ( seeley , 1995 ) . in essence , the rate of unloading of water foragers indicates the colony demand for water ( i . e . the feedback system is similar to that for nectar ) . in this way the balance between collection and consumption of water is maintained . importantly , water collection does not interfere with the collection of concentrated nectar by the colony ( kuhnholz and seeley , 1997 ) . the first bees to start water collection may be stimulated by the collective increase in crop sugar concentration of all bees in the nest , due to trophallaxis ( lindauer , 1955 ; seeley , 1995 ) , or possibly by the collective increase in haemolymph osmolality . apart from environmental factors , the tendency of honeybee foragers to collect water , nectar or pollen has a genetic component ( hunt et al . , 1995 ) . workers with the lowest sucrose response thresholds , i . e . those able to distinguish low sucrose concentrations from water in proboscis extension response tests , become water foragers ( pankiw and page , 2000 ) .
water foraging is regulated according to current demand and water is not stored in combs by temperate honeybee colonies : this is because nectar availability fluctuates widely and water sources usually do not ( seeley , 1995 ) . for african honeybees , occasional water storage has been recorded in wild bee nests , as after summer rain in the kalahari desert ( eksteen and johannsmeier , 1991 ) . park recorded temporary storage of water in the crops of ` reservoir bees ' ( park , 1923 ) .
studies on the mechanisms by which bees thermoregulate in flight have yielded data on the relative magnitudes of metabolic water gains and evaporative water losses for bees as individuals . metabolic water production by large flying bees ( xylocopa and bombus ) is substantial ( bertsch , 1984 ; nicolson and louw , 1982 ) , especially at low or moderate t a . honeybees ferrying large water loads to the hive at high t a produce enough metabolic water to offset their evaporative water losses ( louw and hadley , 1985 ) . however , it cannot be assumed that metabolic gains will balance evaporative losses in flight . because variation in metabolic heat production is used by bees ( apis and centris ) as a primary mechanism of thermoregulation in flight ( roberts and harrison , 1999 ; roberts et al . , 1998 ) , at high t a metabolic water production will decrease as evaporative water loss increases . for individual bees , the thermal environment is crucial to water balance in flight .
bees engaged in brood warming generate metabolic heat using their flight muscles . at low t a , the metabolic rates of incubating bumblebees are extremely high ( heinrich , 1974 ) . honeybee brood nest temperatures are maintained constant at about 35°c by bees that ` shiver ' on the comb surface or inside empty cells in the brood area ( kleinhenz et al . , 2003 ) , and high metabolic water production can be assumed during this energy - intensive heating activity . however , the general colony heat production to which all workers contribute does not require much increase in metabolism ( harrison , 1987 ) .
in flying a . mellifera and centris pallida there is a negative relationship between water balance and t a , the bees being in negative water balance at t a above 31°c ( roberts and harrison , 1999 ; roberts et al . , 1998 ) . although the cuticular permeability of both species increases with t a , neither cuticular nor respiratory water losses are sufficient to explain the very high evaporative water losses at high t a . these probably involve cooling mechanisms such as regurgitation of crop contents onto the proboscis ( heinrich , 1980 ) . this ` tongue lashing ' at high t a has been observed in a variety of bees ( roberts and harrison , 1998 ) and in honeybees has been shown to increase evaporative losses dramatically ( louw and hadley , 1985 ) . as a result , the thoracic temperatures of nectar and water foragers are significantly lower than those of pollen foragers ( cooper et al . , 1985 ; feuerbacher et al . , 2003 ) .
the amount of water that has to be evaporated from dilute nectar is enormous ( fig . 2 ) . in order to increase the sugar concentration from 20 % to 82 % , bees must evaporate 0 . 75 g water for every 1 g of nectar collected , and the mass of honey produced from a given mass of nectar is correspondingly reduced . recently we have shown that foragers of a . mellifera scutellata collecting dilute nectar of aloe greatheadii var . davyana in dry winter air begin to concentrate the nectar before returning to the hive ( nicolson and human , 2008 ) . because the crop is impermeable to both sugar and water , we can only explain the doubling of crop sugar concentration , from 20 % to 40 % , by evaporation on the tongue . this contradicts the conventional wisdom that the concentration of nectar is unchanged during its transport by bees between flowers and the hive ( park , 1932 ) . the advantage for the bees lies in reducing the water load that has to be carried and the amount of evaporation needed in the hive ( fig . 2 ) ; the cooling effect is less desirable for individual foragers but disturbances of heat or water balance can be corrected in the hive .
relative masses of sugar and water in nectars of various concentrations and in honey ( horizontal red line ) . the figure shows the nectar - processing advantage for apis mellifera scutellata workers concentrating the nectar of aloe greatheadii var . davyana from 20 % to 40 % on their tongues : two - thirds of the necessary evaporation is achieved before the bees return to the hive ( nicolson and human , 2008 ) .
the various processes involved in cooling the honeybee nest – collecting water , spreading it within the brood comb , and speeding its evaporation by fanning and regurgitation – have been mentioned above . this enables the temperature in the brood area to be precisely regulated at 35°c , but humidity in the hive is less constant ( human et al . , 2006 ) . air in the hive will generally be more humid than outside , as a result of transpiration of the inhabitants and evaporation during nectar flows . while high humidity is necessary for brood development , a dry atmosphere favours nectar ripening . we have measured absolute humidity ( thus excluding temperature effects ) in various regions of the hive , and found higher values in the brood area than in nectar stores , suggesting adjustments by the bees ( human et al . , 2006 ) . however , trade - offs with regulation of temperature and respiratory gases will disrupt the establishment of optimum humidity levels .
colony level respiration is important in social homeostasis . periodic synchronised fanning leads to tidal ventilation in honeybees and stingless bees when only one nest entrance is present ( moritz and crewe , 1988 ; southwick and moritz , 1987 ) . measurement of cyclic fluctuations in water vapour pressure and temperature at the nest entrance would enable estimation of evaporative water losses at the colony level .
the non - random disposal of the excreta of social insects , such as ejecting faeces late in larval development , is assumed to be for hygienic reasons ( weiss , 2006 ) . in honeybee larvae , the midgut–hindgut junction is occluded until the end of the larval stage , and defaecation coincides with cocoon formation , the excreta being incorporated into the structure of the cocoon ( jay , 1964 ) . healthy adult apis do not defaecate in the nest , even during overwintering in temperate climates ( but defaecation in or around the nest is a sign of infection with the midgut parasite nosema ) . defaecation flights occur when weather permits , and until then rectal fluid may be stored for prolonged periods , the distended rectum occupying much of the abdominal cavity ( fig . 3 ) . obviously an individual honeybee ' s water content fluctuates enormously depending on the volume of crop or rectal contents . an inverse relationship between crop and rectal volumes has been measured in honeybees confined for varying times after feeding ( roces and blatt , 1999 ) .
mass defaecation flights are conspicuous in tropical honeybees , and led to the ` yellow rain ' scare , due to the high proportion of pollen exines in the faeces ( mardan and kevan , 1989 ) . heat - shedding benefits have been suggested for the giant honeybee apis dorsata , which builds exposed combs and engages in mass flights involving half the colony , each bee jettisoning 20 % of its body mass ( mardan and kevan , 1989 ) . however , more comprehensive recordings for the same species show that mass flight activity is highest during maximum brood production , and timed so that brood temperature is minimally affected by the temporary absence of the protective curtain of bees ( woyke et al . , 2004 ) . water shedding may be a more important function of mass flights than heat shedding .
bees are less subject to desiccation than most terrestrial insects . this is because their nectar diet and high metabolic water production during flight frequently generate excess water . water fluxes in the honeybee colony are also high , due to honey ripening and periodic water demand for evaporative cooling and for feeding the brood . very importantly , the favourable microclimate created by the nest architecture and its densely aggregated inhabitants reduces evaporative water losses and provides a hydric and thermal refuge for returning foragers .
honeybee abdomen showing full crop ( a ) or full rectum ( b ) . adapted from plate 8 in dade ( dade , 1962 ) .
workers of apis mellifera do not forage for themselves and in social bees there is a blurring between the individual and colony in terms of water balance physiology . common to water regulation at both the individual and colony level is the regurgitation of nectar or water on the tongue for evaporative purposes . this is involved in water elimination from nectar both in the hive and during foraging , and water is evaporated in the same way to cool either the hive or the individual bee in flight . heinrich has previously drawn attention to the similarities in individual cooling , nest cooling and food storage behaviours ( heinrich , 1985 ) . perhaps these all originate in bubbling ( a term i prefer to tongue lashing ) , which appears to function as a nectar - concentrating mechanism in a variety of bees , and may have a profound influence on the water balance physiology of solitary bees in addition to social homeostasis . the high propensity of bees for regurgitation is important in both trophallaxis , which is not confined to highly social species ( kukuk and crozier , 1990 ) , and bubbling to evaporate water .
i thank julian dow for inviting me to contribute to this volume , connal eardley for identifying allodapine bees , and christian pirk for commenting on the manuscript . the paper is dedicated to simon maddrell and his enduring fascination with water in insects .
cooper , p . d . , schaffer , w . m . and buchmann , s . l .
) . pollination of the yellow passionfruit : nectar , pollen and carpenter bees .
cortopassi - laurino , m . , inmperatriz - fonseca , v . l . , roubik , d . w . , dollin , a . , heard , t . , aguilar , i . , venturieri , g . c . , eardley , c . and nogueira - neto , p .
feuerbacher , e . , fewell , j . h . , roberts , s . p . , smith , e . f . and harrison , j . f .
) . effects of nectar concentration and flower depth on flower handling efficiency of bumble bees .
) . the composition of larval food in stingless bees : evaluating nutritional balance by chemosystematic methods .
hendrichs , j . , cooley , s . s . and prokopy , r . j .
) . post - feeding bubbling behaviour in fluid - feeding diptera : concentration of crop contents by oral evaporation of excess water .
human , h . , nicolson , s . w . and dietemann , v .
hummon , a . b . , richmond , t . a . , verleyen , p . , baggerman , g . , huybrechts , j . , ewing , m . a . , vierstraete , e . , rodriguez - zas , s . l . , schoofs , l . , robinson , g . e . et al .
hunt , g . j . , page , r . e . , fondrk , m . k . and dullum , c . j .
johansson , t . s . k . and johansson , m . p .
kleinhenz , m . , bujok , b . , fuchs , s . and tautz , j .
kovac , h . , stabentheiner , a . , hetz , s . k . , petz , m . and crailsheim , k .
) . uber die einwirkung von duft - und geschmackstoffen sowie anderer faktoren auf die tänze der bienen .
moritz , r . f . a . and crewe , r . m .
moritz , r . f . a . and southwick , e . e .
) . the importance of osmosis in nectar secretion and its consumption by insects .
) . simultaneous measurement of evaporative water loss , oxygen consumption , and thoracic temperature during flight in a carpenter bee .
) . effect of nectar on microbial antagonists evaluated for use in control of fire blight of pome fruits .
roberts , s . p . , harrison , j . f . and hadley , n . f .
( hymenoptera : apidae ) and the ecology of nectar intake by bee colonies in a tropical forest .
) . inner nest homeostasis in a changing environment with special emphasis on honey bee brood nursing and pollen supply .
schmid - hempel , p . , kacelnik , a . and houston , a . i .
) . social foraging by honeybees : how colonies allocate foragers among patches of flowers .
southwick , e . e . and moritz , r . f . a .
) . warm - up rates and body temperatures in bees : the importance of body size , thermal regime and phylogeny .
visscher , p . k . , crailsheim , k . and sherman , g .
) . evaluating responses of honeybees to sugar solutions using an artificial - flower feeder .
) . behavioral , ecological , and physiological determinants of the activity patterns of bees .
woyke , j . , kruk , c . , wilde , j . and wilde , m .
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regulation of energy and water are by necessity closely linked in avian nectarivores , because the easily available sugars in nectar are accompanied by an excess of water but few electrolytes . in general , there is convergence in morphology and physiology between three main lineages of avian nectarivores that have evolved on different continents – the hummingbirds , sunbirds and honeyeaters . these birds show similar dependence of sugar preferences on nectar concentration , high intestinal sucrase activity and rapid absorption of hexoses via mediated and paracellular routes . there are differences , however , in how these lineages deal with energy challenges , as well as processing the large volumes of preformed water ingested in nectar . while hummingbirds rely on varying renal water reabsorption , the passerine nectarivores modulate intestinal water absorption during water loading , thus reducing the impact on the kidneys . hummingbirds do not generally cope with salt loading , and have renal morphology consistent with their ability to produce copious dilute urine ; by contrast , as well as being able to deal with dilute diets , honeyeaters and sunbirds are more than capable of dealing with moderately high levels of added electrolytes . and finally , in response to energy challenge , hummingbirds readily resort to torpor , while the passerines show renal and digestive responses that allow them to deal with short - term fasts and rapidly restore energy balance without using torpor . in conclusion , sunbirds and honeyeaters demonstrate a degree of physiological plasticity in dealing with digestive and renal challenges of their nectar diet , while hummingbirds appear to be more constrained by this diet .
nectar has been described as ‘the simplest food on earth’ ( martínez del rio et al . , 2001 ) , but nevertheless may pose significant physiological challenges for animals feeding on it . since we reviewed the topic a decade ago ( nicolson and fleming , 2003b ) , researchers in the americas , africa and australia have made substantial progress towards comparing the physiology of the three main lineages of specialized avian nectarivores : the hummingbirds ( trochilidae ) , sunbirds ( nectariniidae ) and honeyeaters ( meliphagidae ) ( fig . 1 ) . numerous other bird families show varying reliance on nectar ( nicolson and fleming , 2003b ; symes et al . , 2008 ) , but this commentary will focus on how the main radiations deal with the challenges of nectarivory , highlighting both convergence and differences in their responses .
the relatively low concentration of bird nectars [ compared with insect nectars ( pyke and waser , 1981 ) ] is the fundamental reason for the physiological problems associated with a nectar diet . flowers visited by hummingbirds and sunbirds produce nectar averaging 10–30 μl in volume and 15–25 % w / w ( 0 . 5–0 . 8 mol l −1 sucrose equivalents ) in concentration [ while flowers visited by generalist birds produce nectars that are even more copious and dilute ( johnson and nicolson , 2008 ) ] . nectar can also be diluted by rainfall events . the challenge of drinking dilute diets is that the birds must handle large volumes of preformed water , necessitating fast transit times ( i . e . time for food to pass through the gut , thus minimizing mass gain , which would interfere with flight ) , and yet maintain high assimilation efficiency , while also warming this large volume of fluid to body temperature . more concentrated nectars are likely to be less problematic , because switching between plants would enable birds to access more dilute nectar and thus balance water intake . the other major challenge is that nectar also contains very little by way of other solutes ; nectarivorous birds therefore have to deal with low electrolyte intake as well as low nitrogen , although their nitrogen requirements are relatively low ( tsahar et al . , 2006 ) .
it might be predicted that the physiological constraints of a ‘simple’ nectar diet would result in convergence in physiological responses of the different lineages of nectarivorous birds . however , recent findings indicate that this is not always the case and we now know that these birds show interesting differences in response to their nectar diets ( fig . 2 ) . in the first half of this commentary , we examine some common strategies for dealing with the challenges of a nectar diet . in the second half , we examine available data that indicate differences in how hummingbirds , sunbirds and honeyeaters deal with these challenges .
) , this field is receiving renewed attention , and not without controversy . rico - guevara and rubega (
) presented morphological measurements of hummingbird tongues and high - speed videos of drinking that showed that the tongue traps liquid as a result of surface tension ; this requires no energy expenditure by the bird and does not involve capillary action , which suggests that viscosity is not important . this finding was disputed by kim et al . (
) , who used a modeling approach to differentiate between different modes of nectar drinking , showing that the ‘capillary suction’ mechanism used by hummingbirds , sunbirds and honeyeaters is associated with optimal concentrations in the range 30–50 % ( 1 . 0–1 . 8 mol l
sucrose ; much higher than natural nectar concentrations ) . after further theoretical and experimental analysis of drinking in ruby - throated hummingbirds ,
the methods / techniques used to study the interactions between a substance and the body from administration to excretion ( absorption , distribution , metabolism ) .
in addition to concentration , nectar volumes are important for tongue loading . the volume of nectar determines its height in tubular floral corollas , and partial immersion of the tongue is common ( kim et al . , 2012 ) . when honeyeaters and hummingbirds feed from tubular artificial flowers , the amount of nectar loaded per lick increases with greater nectar volumes or shorter flowers , both of which increase the contact between tongue and nectar ( collins , 2008 ) . however , honeyeaters also commonly extract nectar from open , brush - type inflorescences and the effects of inflorescence shape on feeding rates have yet to be investigated .
specialized avian nectarivores from three lineages . ( a ) whitebellied sunbird , cinnyris talatala ( photo credit : rudi van aarde ) , ( b ) new holland honeyeater , phylidonyris novaehollandiae ( kathryn napier ) and ( c ) charming hummingbird , amazilia decora ( cole wolf ) .
some key physiological differences between the three specialist bird lineages . a representative hummingbird , honeyeater and sunbird ( note the differences in body size ) are shown feeding on nectar of an erythrina species , a major bird - pollinated genus that occurs in the natural range of all three lineages . all lineages show high rates of intestinal sucrase activity ( highest for the hummingbirds ; thicker yellow lines ) and rapid absorption of hexose sugars ( orange arrows ) , but the passerines are capable of shunting water directly through the gut ( blue dotted lines ) and therefore do not only rely on filtration by the kidneys ( blue solid lines ) . * hummingbirds show only a small medullary portion to their kidneys ( shaded green ) , which limits their abilities to produce hyperosmotic urine .
nectar - feeding birds are compensatory feeders over a wide range of nectar concentrations ( martínez del rio et al . , 2001 ; nicolson and fleming , 2003a ) . this means that they adjust their volumetric intake rapidly in response to changes in energy density ( fleming et al . , 2004b ; köhler et al . , 2008 ) . sugar concentration consequently has a marked effect on their sugar preferences . probably because of the rapid transit times and because hexose nectars do not require hydrolysis in order for the sugars to be assimilated , a hexose diet is preferred by both generalist and specialist nectar - feeding birds on dilute diets [ for references , see napier et al . ( napier et al . , 2013 ) ] .
interestingly , most species tested to date show a switch to no preference or even sucrose preference on concentrated diets ( e . g . data for the red wattlebird , anthochaera carunculata , are shown in fig . 3a ) . the concentration at which the switch occurs varies between species , and the minimum sugar concentration at which birds show no hexose preference is significantly correlated with intestinal sucrase activity for 11 bird species , even after phylogenetic correction ( fig . 3b ) ( napier et al . , 2013 ) . birds with no sucrase activity ( e . g . redwinged starlings , onychognathus morio ) or relatively low sucrase activity ( e . g . rainbow lorikeets , trichoglossus haematodus ) prefer hexoses at higher sugar concentrations , while birds with the greatest sucrase activity ( i . e . hummingbirds , but also sunbirds and honeyeaters ) either show no hexose preference or hexose preference on only the most dilute diets ( napier et al . , 2013 ) .