Nat Talk: Understanding Bird Behavior

thanks emma good evening and thank you all for joining us tonight for tonight's nat talk understanding bird behavior with dr wen fay tong i'm judy gradwell president and ceo of the san diego natural history museum and as we look back at the past six months uh since we closed our building in balboa park it's clear that we are so much more than what is inside of our walls in the field our scientists are braving the heat to survey for wandering skippers which are butterflies of conservation concern and i'm happy to report that they found several areas that appear to be teeming with butterflies in other excellent conservation news some of you may have followed the story of our red-legged frog translocation from baja california into san diego and we've just gotten word actually got another email tonight that many of the eggs that we so gingerly transported are now thriving froglets meanwhile our membership department recently implemented a new online series of member meetups and in these interactive q and a's you can meet museum staff and get a view of the work that goes on behind the scenes the next meet up is with our curator of botany john redmond which will be a real treat uh and that's on friday october 9th you can ask him all your burning plant questions you just need to sign up um you just need to sign up for a membership if you don't have one in our education department the staff is just about to launch a roster of online programming that teachers and caregivers will use to bring natural history into the classroom or home and of course none of these activities would could take place without your support the tickets you purchased tonight your donations and your facebook shares all help our mission to thrive during this time and we thank you mightily so on to tonight's talk the 2019-2020 season of nat talks is made possible by presenting sponsor the downing family foundation and media partner kpbs the public media station serving san diego and imperial counties tonight's speaker is dr wen fei tong is a biologist with a passion for understanding and conserving the natural world who enjoys sharing her love of birds and biology through her paintings photography teaching and writing she grew up in singapore where she started birding at 12. she first got hooked on field biology as an undergraduate at princeton and oxford and has a phd in evolutionary biology from harvard where she is a research associate she has taught at universities of montana and alaska anchorage where she wrote her first book bird love she has guided natural history tours in tanzania the galapagos and montana where she owns a tour company and takes visitors birding on horse pack and i understand she's in montana speaking to us tonight so welcome gwen fay hi everyone thanks so much for that lovely introduction judy and thank you everyone for coming tonight it's really exciting to share my love of birds and to just tell you a bit about why i got interested in bird watching and why i wrote these two books if i can start the slideshow there we go so this is a mangrove pitter and it's one of my favorite words i should say that all the pictures all the photographs and illustrations in this talk are mine because we've got a copyright issue with the books being with with the talks being broadcast and death on facebook so i thought it would be easier just to use my own things and then not have to worry about the publishers and so this is just an example of one of the things i love about bird watching which is that there's always this feeling of being on a slight hunt for something and this bird is very very shy and secretive even though it's so beautiful and colorful and so i've got a big kick out of looking for this bird that's one element of bird watching which is a lot of fun if you do like to spend time outdoors but you want a little more excitement than you would typically experience just wandering around and not knowing what you're looking at and the other thing that birds mean a lot to me for and have for a long time is that i've grown up really thinking a lot about the similarities between humans and other species and so this is a slide from the last bit of my acknowledgements in my phd talk and it's traditional for students to acknowledge all the people and thank all the people that help them and usually people have photographs but i didn't really have photographs of people because i spend all my time photographing animals so what i did was draw all the people that i wanted to thank as animals that i associated them with and i just wanted to mention the saturn bow bird on the top left corner which is one of the professors who really inspired me a lot because he wasn't just he passed away last year henry hall but he wasn't just a fantastic scientist with a real thirst for understanding natural history and you could go for a walk in the woods with him and he would tell you every single tree and every single bird and little spider you were seeing but he also had a wonderful creative knack with both math mathematics and art so he one of his books is the adaptive geometry of trees and i drew him as a satin bowel bird because he's so he's an artist as well he was an artist and he would do all these terrific little renditions he he carved some bits little animals out of driftwood and took them to the grand canyon and photographed them and set up things for k-12 education looking at his little wooden animals going and i've gone by henry for ages but let me switch to saturn bowel birds uh these are fascinating birds because they build these architectural structures and they essentially collect a lot of beautiful belongings including especially blue which matches their feathers so they seem to have a preference for blue and if they can't find enough blue objects like berries they'll find blue bottle caps from tourists and they'll line the the the surroundings of their bowel with these lovely collections of objects like like a museum curator or an interior designer or something would do and they use that whole structure to lure females in and the idea is it's not a nest at all this is just the way to attract females and there's been wonderful experiments where people look at this the intelligence of the male bowel bird not just how beautiful his structures are or how shiny his plumage is but how good he is at problem solving and it turns out that the males that are better at problem solving are the ones that get more females attracted to the nest so that's just an example of the fun experiments that i try to talk about in my book as well as what birds mean to me uh some other things that they mean to me which i hope to get across in the books is that they symbolize the seasons a lot and they sort of root me all the time so i i'm starting to sound like a religious prosperitizer but here's a yellow warbler that i took a photo of just north of boston massachusetts and so one thing they do is herald spring and i found them a great solace and comfort during the pandemic because i was in new york city at that time and even in the middle of new york actually in the middle of a big city like singapore where i grew up you can find birds everywhere and you can hear them and so these are little sketches that i did to to cheer myself up during this this spring during the pandemic because i would go take my dog in the walk in the park every day and see all these robins building their nests so it's carolina friend that would be singing in exactly the same spot every morning and so these birds became very much like neighbors and i find that happens almost everywhere i go and that's a really fun and enjoyable aspect of getting to know the birds wherever you are especially in your backyard so in both books i try to talk not just about very exotic birds which i will have in this talk as well but birds that everyone should be familiar with in their backyards wherever in the world they live oh so that's the two books just so you have a search image and since most of this audience i think is from san diego i thought i would share some of the photographs that i took in san diego about 10 years ago i realized now it's the last time i visited and these are i think all taken an ocean side so here's a brown pelican and i'll come back to brown pelicans again later in the talk but one of the things i try to bring out in understanding bird behavior is the fact that a lot of people in biology now are starting to have the ability to study birds as individuals and i really enjoyed this pelican because he or she was having a terrific time cleaning cleaning itself instead of just splashing in the water happily you can see it's so expressive this bird looked so pleased with itself just just splashing its wings in the water and i'm sure it was having fun so there's a lot of borderline anthropomorphic language that i use in the book and i think that's intentional because personally i don't see a great difference between humans and other species and a lot of the hormones and the emotions that we feel as a result of those hormones are very deeply conserved evolutionarily so i think there's a good scientific reason for identifying strongly with other species such as birds this is a says phoebe that i saw in the same beat um on oceanside and i put it here because i recently went up a mountain in montana and saw a pair of save phoebes right at the top of that mountain because i i don't know exactly what they were doing but they looked like they were flying at each other and having a little disagreement and so it's just terrific to me that the same bird can be living and breathing all the way in san diego on the near the coast as well as on the mountaintop in montana and uh closely related bird the black phoebe also on the same beach i this is slightly cornered but i put the slide in to remind myself that even though i use a lot of anthropomorphic language and my whole purpose is to get people to identify with birds i do want to stress that there's nothing moral about oh they're no moral precepts to take from anything i talk about or any of the examples i use so the the point is that evolution and nature in general are completely amor there's there isn't uh should or shouldn't involved in in any of the examples i use you you'll see why i'm saying this because things get a bit gory uh so so just to start the last thing i wanted to bring up to people's minds is because i'm trained as an evolutionary biologist and this is a photograph i took in northern kenya with mount kenya in the background and it's where i first started being a field biologist studying separates actually in this place this field center called impala and in the foreground we've got a lot of little nests in the acacia tree so one of the things i'd like everyone to keep in mind is just this idea that we share a very deep evolutionary history with all the birds that i'll talk about are in the books and so every time you ask questions about why there's such a diversity of behaviors and why birds behave the way they do it does tell us something about our own behavior and why that evolved as well and so here for instance you can ask why these social grey cat social weavers are nesting in a group as opposed to other birds which less singly don't don't build their nests in clumps and i i answer that question i think at least one of the books so i'll just zoom in on one of these nests to give you an idea of what the bird looks like it's the what you call a cooperative breather so we actually see evidence of members from previous clutches so grown-up children coming back to help the parents with these nests and here's another nest that i found in that i used to study in africa and this is from zambia i did a lot of my postdoc work but i just wanted to take a moment for you to look for the nest in this photograph and obviously it's dead smack in the center but the fantastic thing about this nest is you'll notice that it's built from living drafts and so i'll cut to a photograph of the aerial view of the nest so you can see what it looks like from the inside this nest of a very very drab little brown job bird called the rattling cysticular and cysticles are specific to the old world but they're the sort of bird you would just walk past and unless you were a really keen bird you would not want to be trying to id this thing because really cysticus is our best id from their from their songs they have fantastic names they're rattling cysticlis croaking cysticlines siblings sticklers um all sorts of funny names but anyway this is what the nest looks like from above so you can see that it's been the bird has basically stuck the growing grass stems together from within using bits of spider silk and various insect cream silks and then lined it with its feathers and so these are fascinating nests to look for because they're really hard to find and we had to get a lot of local children to help us find them so i thought one one of the things the books does is to try and explore the diversity of behaviors including architectural structures that birds are capable of building such as these nests all the way to the classic bird nest that we see from something like the american lobby and here's a lovely behavior that the robin's performing where it's essentially taking a little pool packet from its cheeks and it's about to fly out of the nest with that but a lot of birds do that to keep the nests clean i do have i think some examples of other ways in which birds keep the nest clean but also have the chicks deter predators by shooting nasty substances at them or shooting their pool at predators which i always find entertaining as well um another aspect of nesting of course is finding the nest hole so this is another sketch i did in the spring when i was watching this pair of wood ducks looking for a new home and on the first line you've got the female on the left and they're very colorful and gaudy male 1 right she's being mobbed by a starling so one of the other behaviors i talk about is this mobbing behavior which is where birds attack and some something that they consider a source of danger and i just thought it was fascinating watching these birds interact with this large tree because all its nest all the existing cavities industry were already occupied by starlings and skinhead wood duck really liked its tree but it's like she couldn't find any available real estate it reminds me of all the new yorkers of whatever fleeing the big cities and looking for somewhere to put down routes in more rural places like missoula montana and gosh the housing market is crazy right now so so she she was looking and looking and looking at all these tree holes and the poor male was waiting but no luck i think at least while i was watching them so there's nests where individuals look for the nest together but there is also nests as a form of courtship and here's a male beaver also in zambia who has built the nest as part of a way to get a female interested and the females will come and inspect these potential holes these potential places to be other chicks and if they're not satisfied they sometimes tear them out which is not such great fun for the male but this this one looks quite good so i think he ended up with someone of course there also lots of other ways that birds choose mates so here's a pair of barn swallows and i took this photo in montana as well so you'll notice that the male piece in front is very reddish in on his belly and his breasts and whereas if you look at barn swallows in australia or asia or europe you find that they tend to be much paler almost snowy white gleaming white in front and the barn swallowers are very easily distinguished from other swallows because they have these beautiful long tail streamers so there was an experiment done a few decades ago where people snipped off the tail ends of these tail feathers on nails and then glued them back on and used that to artificially lengthen or shorten the tails and then they had a control as well which had the same length tail and they looked at how many children those males had and they found that if the males had artificially longer tails they had the most children so they were the sexiest males and so this is the argument for why you have what we call sexual selection for very extreme characteristics such as extremely long tail feathers which are not very aerodynamically sensible so it makes it harder for the bird to maneuver to catch insects or escape from predators or something but it makes him sexier and it gives him more children what was fun about this is i'll get back to trying to explain the difference between european bond swallowers and north american barn scholars people ex repeated this experiment in north america and they found that the females really didn't care about how long the male band swallowed tails were so that left everyone scratching their heads right it's like there's this beautiful elegant experiment and the females don't care who which happens a lot in science actually and they found out that it was really the color of the male's value that the females like and so if you artificially apply rouge to a barn swallow male's front chest front he gets more offspring in north america but the north american females don't seem to care so much about his tail feathers and that explains at least it's consistent with the geographic variation we see whereas where north america you have males that are very reddish in front and have relatively short tail whereas in europe where the females like longer tales but don't care about the color of the shirtline they they have longer tails and they're very frightened fun there's also i try to cover a lot of because for most birds the males such as the wood ducks and the barn swallows are the sugary ones and they do a lot of showing off to females these are wilson's fowler ropes which are type of strawberry and the more colorful larger slightly larger bird that's right in front is actually a female whereas the other two behind her are male and so this bird as well as a few others are examples of what's quite rare among birds but what we call embellishing a sex role reversal and so i try and talk about why in a very small number of species you see larger showier females that fight for the males and actually leave most of the parental care most of the child cared for males and when that tends to occur and this is just a close-up of a female fallable so she's she's definitely the more colorful one and she'll fight off other females for access to males on the other end of the spectrum which is more of what we're familiar with is all these dinosaur like very very competitive males and so this is a dusky grass that was male that was charging you and they get really amped up on hormones in the summer and i think this poor grass ended up being run over because he would charge anything that came into his territory including cars probably but the chickens are the whole chicken orders just fascinating and i did want to mention that birds are the only living dinosaurs i'm sure most of you already know that but this kind of encounter with birds as well as being charged by things like turkeys always makes me think of it always reminds me of the fact that birds really are dinosaurs if anyone keeps chickens you probably feel this every day this is a sharp tail grass display and so they're very closely related to prairie chickens and they have this fantastic colored throat skin that they puff up and they actually spin in little pirates with the little sharp tail sticking up in the air and it's fascinating to watch these grass lack because they do something called lecking which is a special behavior where several males gather on a dancing ground and they display to females on mass and it's very easy for the females to then decide who they think is the most attractive male so from both from the male's perspective this is best for the the male that gets all the matings the most attractive male but it's a very interesting mating system in the sense that it's a winner-takes-all situation so either you're the most attractive male and you get 99 of the meetings or you're on the periphery and no one's interested in you and there's another very interesting experiment done this is a black grass but same same group of birds this is the european example and biologists didn't experiment with these black vows because they were wondering okay what causes this crazy skew in reproductive success where one male is the winner who takes it all and they found that these female grounds actually follow fashions so you can do an experiment where you put a lot of stuffed females around one male and you create a heartthrob you turn him into the pop star of the night or the pop star of the season because all the other females see that he's getting more attention and that's one of the cues one of the rules of thumb that they use to to decide to to make them which i is another brilliant experiment i think um and i just thought i would stick in a domestic chicken since this was actually taken in my parents yard in my parents garden a few years ago and the red jay jungle fall which is the ancestor of all domestic chickens is from malaysia or from that sort of southeast asia area and they're beautiful birds so i just thought i'd stick this in there okay um cutting from courtship to to what goes on after courtship this is a very common backyard bird in australia it's called the superb very red and they're fascinating for lots of reasons so they pop up in the books again and again but what i've got them here for specifically is the male who's the showy one again in this case is displaying to a female with a little flower petal and in this case unlike the satin bar birds that like to choose colors that match their plumage superb fairy runs like complementary colors so they tend to prefer yellow orange to to show off their beautiful blue feathers and it turns out that these birds win the guinness book of records for infidelity so up to three quarters of the chicks in a given nurse are not fathered by the male who's caring for them and who is bonded very closely to the female that that is their mother and so barley just are wondering when these extra pear populations were taking place and it looks like the females from radio tagging the female the females are actually sneaking off just before dawn to whichever neighbor most attracted them and having a little extra pair of liaison and then coming home and because they're all doing it oh and all the males are doing this too it's just sort of russian roulette situation but what i found fascinating about this example is the males only display with flower petals to their neighbours they don't do it to their long to their long-term partner they just do it to the the ones who whom they want to have an extra pair cooperation with but the females make the ultimate judgment on that i also talk um i'll cut from all the reproductive behavior direct reproductive behavior and talk about birdsong so this is a western meadowlark and it's one of my favorite favorite songs because it evokes feelings of just freedom and grasslands and riding horses across open prairie and i one of the reasons i bring up birdsong a lot is it is used for courtship as well as territorial behavior but it's a fascinating example of culture in animals other than humans and this is a white throated sparrow no sorry white crown sparrow and i took this filter in san diego as well on the same trip as i took the other bird san diego bird photos but these north american styles are one of the best examples we have of different different geographic accents essentially so males from a particular part of north america or even a particular part of california will sound will have their own regional dialect and their songs will sound distinctly different from males in another place and this is because these birds learn their songs from a tutor just as they're growing up and it's very analogous to how human children learn language if you miss this sort of sensitive period where they're most receptive to their native song they won't ever learn it again once they've passed that developmental period which is a bit like children if you don't learn a certain language at a particular age you it's very different from learning a language as a second language as an adult completely different parts of your brain are involved and things like that um there's also a lot about social behavior outside of portrait and outside so similarly to how i said the a lot of songbirds use song for territories i thought i'd bring up ravens as an example of how individuals are so smart that they keep tabs on the relationships between other individuals so it's already quite sophisticated to know what all your neighbors sound like and to sort of you know birds really like to explore investigate if you if you do a playback and some birds do this to trend your bird in you you play a song and that bird is especially keen to investigate because it knows that your phone or your your playback device doesn't sound like one of the neighbors it's familiar with so it's most birds are able to remember individuals based on their song what's really cool about ravens is they don't just remember other individuals they remember how those other individuals know each other how strong their relationships are what kind of relationships they have and we know this because ravens formed these very strong monogamous pair bonds and once they found their partner for life they settle down on a territory and they defend that vigorously but until that stage until about five years or so however long it takes them to find their partner they go through a period of this is a bit like humans going to bars or something to try and find a trying to find a partner they they go through a lot of little friendships and they go through different stages of these budding friendships and so it's not in the interests of a power couple of ravens who already have their territory to have other competitors of strong long-term couples around because then they have to fight for kill fight for access to scavenge kills when they scavenge and things like that so what they do is they keep tabs on these younger ravens and if they see that there's a pair that's really starting to become very close they sabotage them they don't bother to sabotage their budding relationships of much younger more casual couples they they specifically pick on the ones that are about to become the next power couples and they they go in and break it up they see them building and cooling i found that a really cool study there's also less or more simple-minded birds that are very capable of having complicated relationships in their heads too so these are vulturine guinea fowl closely related to the helmeted guinea fowl that most people will be more familiar with and they're more arid adapted so these are birds that i saw a lot in kenya in the same place that i showed you that earlier photo of with my kenyan background and these birds tend to form flocks of about 60 individuals and so you would think that within that flock of about 60 everyone just knows about them has no stronger relationships but by tagging every individual bird these biologists found the max planck found that they actually have little subclusters of relationships so you'll have a couple of families that prefer to spend time together and they'll actually spend most of their time feeding and less roosting near each other within that group of 60 birds so it's a bit like within your neighborhood you might have a couple of families that you tend to spend more time with even though you do a lot of things in the same area as all the people in the same neighborhood as you there's also very sophisticated forms of social behavior with what we call cooperative breathers which is what the superb fairy brands in australia do as well these are acorn woodpeckers which you have quite a few of in california as well as in arizona bits of mexico and in certain parts of their range acom woodpeckers form these large groups which breed together and also form acorn ladders together which they guard together so what i've tried to draw here is a little cluster of acorn woodpeckers at one of their granaries one of the granary trees where they hammer bespoke custom-made little holes for every acorn that they collect and then they jam it into the hole and that's their way of keeping the acorn fresh for the for over the winter and they'll have several trees if it's a big group and millions of acorns and the larger the group the better they can amass these ladders as well as defend them against other groups rival groups and with this system it's just fascinating because with the cooperation comes a lot of internal conflict as well because you find that multiple females multiple pairs share a singleness and so even though they're cooperating to to incubate the eggs and to raise the cakes and to guard their granaries they also have a lot of conflict because it's in everyone's interest to have more chicks in a particular nest than the other people than the other birds in the group so females actually chuck each other's eggs out until they've started laying themselves at which point they stop because they might chuck their own about by mistake so there's a lot of conflict and there's a lot of internal destruct disruption and destruction as well as the cooperation which is a tension i find very interesting in multiple species on a less sophisticated note these canada js and closely related stability which you get in europe and asia also form cooperative breeding groups but they're less they're less complicated than what the e-commerce packages do so here it's more the case of again finding it hard to get any available railing state because everything's filled all the territories are filled and in those situations young birds will stay behind even though they're fully mature and sexually mature they just can't find the territory so they'll glom on to an existing pair and help them amass food for the winter and help them raise their mix sometimes help them raise the next batch of children and they'll do this even with unbelievable birds uh in terms of child care i just thought they'd show these covers because a lot of shorebirds have very much very high variation in who takes care of the children and that's partly because the offspring the chicks are so what we call precocial they're fluffy and they can run around within minutes sometimes of hatching and so they're quite independent and they don't require a great deal of care and as a result the parents sometimes in some species will try to be the first to leave so that they just leave their partners the single parent and biologists have found from looking at the sex ratio of the parents that whichever sex is rarer and therefore going to be in high demand and finding going to find it easier to find a new partner is the one that's more likely to abscond and in a lot of populations this happens to be the female and so since she's rarer she's it's going to be easier for her to find a new mate she actually leaves first and then leaves the father to take care of the offspring and just finds another male and sets up sets up home all over again with a new guy but that varies from population to population which is one of the themes that i can bring up in the book where we're getting to the point where instead of treating all birds from one species as a stain we're looking at population differences as well as individual differences there's also the strategy of just dumping your children on another pair altogether so in this common meganza species but it's very common to see common mechanisms with about 20 duck things and that's not possible for one female common meganza to have laid off his eggs but it's very commonly the case that other females have snuck a few of their eggs extra eggs into her necks and she ends up raising a huge flotilla of ducklings and again like with the pub lovers these ducklings are quite independent so the marginal cost of an extra duckling is relatively small you don't you don't see this so much with songbirds like robins or sparrows because it's really expensive to raise a lot of naked young very very healthy chicks and that brings me to another strategy that parents have for dealing with well trying to maximize their reproductive output in the long term so unlike things like robins and sparrows where birds start incubating all their eggs at the same time so that everyone grows up at about the same age a lot of birds of praise such as these barn owls both stagger their age of their children and they do that by starting to incubate the moment their first aid is made and so you end up with this crazy size disparity it's not it's life is not really really not very fair for young birds of prey and in times of plenty it's all hunky-dory because everyone there's enough food for everyone but in times where there just isn't enough food to go around it's very usual that the rants don't make it and the you could ask why the parents bother to lay extra eggs at all one one idea is they're hedging their bets in case there's more there's enough food to raise more chicks that yeah it's also hedging their bets because sometimes the first couple of eggs is addled and doesn't hatch in which case the last few are insurance eggs so they're really there just in case the older ones don't make it a slightly darker version of this is siblicide which doesn't occur all the time in great blue herons which is what i've drawn here but it is what we call obligate so in in things like great egrets which are closely related so in something like a great library they almost always have twins and one of them never makes it because it's sibling always kills it so it's really conflict from in the nurse from the start so it's good thing that humans don't do this since it would really be a nightmare right now with everyone staying at home a lot more this is a another it's an adult great for heroin so i thought i'd cut from family life to another theme in the book which is just finding food and i took this photo in north carolina california rather than southern california but it was fascinating to watch this bird because he was walking around in the long grass for a long time and i couldn't figure out why heron was so interested in the long grass and suddenly it came up with this ground squirrel and took it flew it to the water and drowned the squirrel repeatedly until until it was dead and then flew off with it which is how i got this photograph i had a really hard time swallowing it but um i spent quite a lot of time talking about different ways in which birds find food and one of the themes that i try to talk about related to that and this this isn't understanding bird behavior is the idea of convergent evolution so similar or the same solutions to a common evolutionary problem that evolved independently so on the left here we've got birds that i grew up with that are called sunbirds uh although these are two african species and then on the right you've got hummingbirds which all of everyone in north america or the new world will find much more familiar and both groups are nectar feeders and they're very small and they fly very fast and they're extremely colorful and extremely beautiful but what's fascinating is they've independently completely independently evolved to eat sugar and one of my friends figured out how hummingbirds tasted sugar so it's quite rare actually for birds to feed exclusively on carbohydrates like sugar most birds feed on either insects or or seeds and so normally to to find such to feed on something you've got to find it rewarding it's sort of why we find salt and fat so so exciting and why we tend to binge is because we've evolved to find those tastes it's very very palatable and so she had this question of how did hummingbirds evolve to taste sweet things and like sweet things and so she did a lot of very very complicated genetics and she found out that hummingbirds unlike other birds have a sweet taste receptor and they've evolved that from a duplicate copy of the gene for tasting umami which is the sort of taste you get from things like soy sauce this is savoury flavor and birds all birds seem to have that taste receptor but only hummingbirds have converted have tweaked that gene to make a sweet receptor that's that tastes sweet things and so the next question is whether sunbirds which have the same nectar feeding behavior have independently evolved some some other solution or the same solution to taste and sweet uh this is valtrye who is an egyptian vulture and whom i used to love visiting in kenya and he's one of the first examples of tool use in birds and again this is an example of birds finding food so what egyptian vouchers do is they break open ostrich eggs with stones and vulchi was one of the first examples of an animal behavior example of two use although we're much more familiar now with different corvids like crows being very very clever finding food and using cars to run over to open nuts for them and things like that i also just put this up because it gets to my other point about birds as individuals and scientists starting to appreciate that and study that and so here's another example where it's becoming very big enough behavior to start looking at personality and to measure personality in different species and so this is a study that found by measuring the personalities of individual elk as well as individual magpies that the shyest elk seemed to associate the most with the boldest magpies whereas the opposite was not the case at all and what the magpies are doing in this situation is picking ticks off the elk and so the explanation for for this pattern is that the boldest magpies are the ones that dare to actually trance around on elk's back and look for ticks and the shyest elk are a bit too obliging and so they don't mind this they they actually quite like it chris if you've got an elk with a very bold brassy pushy personality that doesn't like having big birds pecking on its back and so it chases them away and similarly the very shy magpies just don't go up to the elk so there's this interesting individual variation in two species as well as a relationship between two species and again on the theme of convergent evolution we've got a similar dynamic going on with a completely different african group of species here we've got red build alex peckers on an amer on an african buffalo and they're picking ticks off as well and we don't know about the personalities of either of these species because no one's done this study yet but that would be interesting to look at and here we've got a north american example so these brown headed cowboys are not after the ticks on the american bison that they're sitting on but they are interesting uh examples of birds that follow they're called tower birds because they would traditionally follow herds of bison and now herds of cows as well for the insects that they flush up and they're converging examples of this in southern and central america where birds will follow large swarms of army ants and and pick off the insects that those army ants drive up as well so there are lots of birds that take advantage of disturbances created by other species the other reason i've got the cowboys up here is they have what we call brute parasites and that means that uh similar to what those common meganzas were doing to other females of the same species these cowboys parasitize the reproductive efforts of other birds but in this case they parasitize completely different species so cowbirds and other birds that do this like cuckoos they common cocoon of coca-cola cuckoo clock fame don't have any of the instincts left to make a nest at all and they don't incubate eggs they don't do any of this parental behavior all they do is find some other species nest in which to lay their eggs and then they may monitor the nest but they leave all the parental care to a different species and this has become a big conservation problem in north america because the cowboys expanded its range a lot since deforestation because of human development and it's resulted in birds like this kirtland's wobbler from michigan uh having evolved zero defenses against a blue parasite like a cowboy and they'll they'll probably sit on a golf ball if you gave that to them and their nurse and as a result these little birds have gone almost entirely they came very close to going extinct for a short time partly because of cowboy parasitism and partly because of uh too much smokey the bear not enough young small pines jack pines that they prefer to nest in so so they've made a good comeback but that was only after a lot of management efforts both killing cowbirds and uh doing a lot of management to get the trees to the right size that these birds like to invest in on the blue parasite theme these are these are back to african birds that i studied the cute green muppet ones are little bee eater chicks and they've almost reached a point of flexing and they're really sweet little birds but they get very heavily parasitized by the the monster in the bottom right hand corner and that's a great honey guy trick and it's this photo is taken probably just minutes or within a day of hatching and so that chick is still blind but you'll notice that it's got this really deadly looking bill hook on the end of its bill and these birds are also brewed parasites and so if those little beaters had been parasitized by one of these great honey guys they would all have been stabbed all the eggs or if there were any chicks chicks would have been stabbed to death by so that the great honey guy chick would be the only one in the nest and the only one getting parental care so that's a very dark side of the species but there's a more interesting well not more interesting but more pleasant lighter side of them as well which is that they're called great honey guides because they guide people to honey and this was first documented in the scientific literature much earlier on by a kenyan scientist but it's been more recently started in mozambique by um and here's a photograph of one of those mozambique honey hunted mozambique and honey hunters with the greater honey guy and that's a wild bird so this is a fascinating relationship where you have a completely wild animal species that can communicate with humans and at quite a sophisticated level so what the honey guy does is it finds the human and it sings a particular song to tell that human to get that human's attention and then it uses that call to indicate to the human where the honey is where the beehives are as well as how close the person is to the beehives and it guides them it guides the humans to the beehives and what the bird gets out of this is they can't really they like eating wax a lot which is another fascinating adaptation we don't know much about but the humans are interested in the honey and so the humans basically help calm the bees with smoke and get the hive down and make the wax available for the birds and in return the birds have basically cut short the hunt for honey for the humans and so there's this very long old relationship which has been breaking down in a lot of parts of africa where increased urbanization because the local people in a lot of parts of sub-saharan africa have stopped listening to the honey guides essentially and it'd be really interesting to know the developmental stages of how a honey guy learns to find humans and communicate with them and we don't really know this yet there's also a lot of communication between birds one of the examples i talk about that i've put here is a japanese tip which is related to chickadees that capture candies that you'll be much more familiar with in north america and all these birds have specific sounds not just to signal alarm but to signal danger different types of dangers so they have a distinctly different alarm call for a snake or a crawling sort of predator versus a flying predator like a hawk and so this bird is taking this photograph this is not my photograph but this japanese title is listening out for and looking out for danger because it's her name called and then my one of the last chapters is about migration and here's where i try to talk more about community science because there's a lot that we can do all the time just by submitting data on the birds we observe in terms of when they arrive at their breeding ground or when they start arriving and i'm sure a lot of you saw the news last week i think about a lot of migratory birds dropping dead and we're not entirely sure why but it could be that that's partly the result of all the forest fire smoke that the birds have inhaled um but anyway here here's a photograph of white stalks the ones that were legendary for apparently delivering babies in europe and there i've got that here because well everyone's attention is probably focused on the bird on the right which has an african hunting sphere through its neck and this is the first documented example we know of in europe that birds migrated so before that people thought in in medieval europe that barnacle geese turned into barnacles in the winter things like that uh they weren't sure where and the swallows ended up in the mud and were overwintered in the mud which is actually quite a logical hypothesis but this stock was shot down in germany with an african hunting sphere through its neck and so survived one 100 to be shot by another but it's it was the first indication europeans had that these birds actually came all the way from africa so they spent half their lives in a completely different place and i just thought i'd end on snow geese which is another of my favorite things to do in montana which is to see the huge flocks of snow geese come through the northern the rocky mountain front in march and onto their way to green arctic and we all know climate change is a huge problem that we should solve collectively so i suppose one of my implicit pleas with these books is that the more people get interested in the natural world as well as in science the more the better chance we stand of making good decisions about our future and trying to save the natural world or trying trying to keep as much of what you love alive as possible and with that i think i'll end and take questions but i just wanted to encourage everyone to support the local bookshop i know a couple of my friends here in montana actually ordered the book from a local bookshop and got it before i did from the publishers so there's a lot to be said for asking your local bookshop first rather than amazing and there's some links that i put up in case you want to look at more pictures or more photographs and more drawings

Channel: SDNaturalHistory

Views: 71

Rating: 5 out of 5

Keywords: san diego natural history museum, natural history, museum, san diego, The Nat

Id: V0pAdmnc-ls

Length: 52min 36sec (3156 seconds)

Published: Thu Oct 22 2020