One of my interests is birding. I am also interested in Boston. Naturally, one or more of these entries will be about birds in Boston. This is the first.
How many birds are there to see in Boston? This is a much more complicated question than it appears to be. What do I mean by “to see,” for example? Do I mean regularly occurring birds that appear in Boston annually? Do I mean any bird that finds it’s way here through a random quirk of fate? Do I mean nesting birds? And what do I mean by Boston in this situation?
As I have discussed previously, I take a fairly expansive view of what constitutes Boston. For the purpose of birding, however, I am circumscribed by the data sets that are available and, for better or worse, the data sets of eBird, the database organized and maintained by the Cornell Lab of Ornithology, are organized by county. So in this instance Suffolk County, which includes Boston, Revere, Winthrop, and Chelsea, is “Boston.” As it happens, this combination of towns is a generous definition of Boston, as the inclusion of Winthrop and Revere add a large stretch of beach and open ocean that is just outside of the Inner Boston Harbor and thus adds a substantial number of species to a comprehensive list of Boston birds. To a birder, Boston starts at the Point of Pines at the estuary of the Saugus and Pines River between Revere and Lynn, and ends at Millenium Park in West Roxbury, a distance of about 16 miles as the crow flies (I know you saw that one coming!)
In this version of Boston, how many birds can one see? The aforementioned eBird is a public database which allows a birder to record the birds he has seen and submit them for inclusion, enabling him to keep track of the location, date, and number of species seen in one trip and over the course of a lifetime. The accumulation of lists submitted by birders in turn generates a set of data which in theory is a simulation of the peregrinations of birds around the globe and over time. It is a a great example of the possibilities of ‘citizen science’ and a database mutually beneficial to professional ornithologists who use the accumulated data to analyze patterns of migration etc., as well as to amateur birders, like myself, who use it to keep a permanent record of all my birding trips, to figure out where the good birding “hotspots” are, and to explore what birds I might reasonably expect to see in a given place at a given time.
As of this writing 26,324 individual lists have been submitted for Suffolk County. According to eBird data, 347 species of birds have been reportedly seen in Suffolk County. The Massachusetts Audubon Checklist for Massachusetts (1998) edition lists “323 regularly occurring species in Massachusetts” as well as 147 “rarities” for a total of 470 species. The eBird database reports 500 species (seriously, exactly 500) have been seen in total by birders who have birded any part of Massachusetts and submitted their lists (over 368,000 lists as of this writing). Since it is clear that there will be some regularly occurring species that will appear somewhere in Massachusetts but not in Boston, it can be assumed that a substantial fraction of the 347 species reported in Boston are “rarities” that are not normally seen and indeed, some would not be expected to occur in Boston at all. For example, the Brown Pelican (Pelecanus occidentalis) is a bird that is found in the warmer climates of the United States. Peterson’s Field Guide to Birds shows the range of the Brown Pelican to extend north up the Atlantic coast to about Chesapeake Bay, with an occasional foray up the Jersey Shore. A similar range map is shown in The Sibley Guide to Birds. Yet there are at least 15 records of a Brown Pelican in Suffolk County in the eBird database. As it happens, a Brown Pelican did show up in Boston for a few days in June, 2012 and this is the date from which almost all the records are found.
So, is a Brown Pelican a bird one can ‘see’ in Boston? I would argue no, as it is a complete fluke that it was here in the first place. To be sure, if I had seen the Brown Pelican in June, 2012, it would appear in my life list for Suffolk County. Yet it is not really a bird that one would reasonably expect to see in Boston, so I would discount it. Another book I have in my possession, Birds of Boston, by Chris Fisher and Andy Bezener, provide a checklist of Boston Birds that includes 316 species, including rare and ‘extremely rare’ birds. Brown Pelicans do not make the list. Incidentally, The Mass Audubon Checklist places Brown Pelicans among the 147 “Very Rare, Accidental, and Extinct Species.”
How then, to determine how many birds one can reasonably expect to find in Boston on a regular basis? Unlike pelicans, there are some species which can be found from time to time in Boston, but are ‘erratic’; that is, they appear every few years in large numbers but some years not at all. A recent example of this was the widely-reported abundance of Snowy Owls in the winter of 2013-14 in much of the northern United States. Some years it is difficult to find Snowy Owls at all in Boston, but in that winter there were dozens of records. These birds, I believe, should count as a bird one might ‘see’ in Boston, but perhaps not every year.
One way to get at this question is to see what people have actually seen over time. Fortunately, the eBird database allows us to determine both how many species have been seen by individuals over time and how many records there are for an individual species. It is possible to generate lists of the ‘Top 100’ birders for a given geographical area. Obviously not all birders submit lists to eBird, but in the absence of hard data about every birder in Boston, this data is to me the most rigorous. In the case of Suffolk County, the top 5 or so birders have recorded between 250 and 300 lifetime species for Suffolk County (The birder with the most species reported has 299 as of this writing), thirteen birders have reported more than 200 lifetime species in Suffolk County, while the 100th ranked birder has recorded just under 100 species. In a given year the top birder might see 200 or more species, and the next four or five usually hover around the 200 species mark. In 2011, a particularly successful year, five birders recorded more than 200 species with one person recording 234 species, the highest number for a single year in Suffolk County. Taking this evidence and the other pieces of data above, it seems the upper limit of possible bird species in Boston is probably in the 300-320 species range. This would include a lifetime of looking for rarities and popping up whenever a new bird is seen in the county, a type of behavior requiring patience, stamina, determination, and a degree of obsession that is, shall we say, unusual. A range of birds one can reasonably expect to see with a lot of work is more likely between 200 and 250 species.
Using the data of actual species recorded provides another way to get at this question. eBird has a feature that allows a birder to create a list of all the ‘Target Species’ in a given geographical region. At the beginning of 2015 I printed out a ‘Target’ list of birds for Suffolk County for the year. This data lists the bird species most frequently reported as the #1 target bird and continues all the way down to the 346th most likely target. (For those of you who notice a discrepancy, that is because a 347th species, Black-backed Woodpecker, appeared in Forest Hills Cemetery and Franklin Park over the winter.) The most commonly seen bird in Boston is the House Sparrow, a 53.57234 % frequency; in other words, House Sparrows appeared on 54% of the 23,486 lists submitted as of December 31, 2014 for Suffolk County, a total of 12,582 times. This may be an under count as many birders ignore House Sparrows completely as unimportant or dull, but it illustrates that the House Sparrow is indeed a very commonly seen bird in Boston.
The 100th bird on the target list is the Turkey Vulture, reported on 2.12893% of the lists submitted, 0r 500 times, again a bird seen relatively frequently in Boston. #200 on the list is the Bay-breasted Warbler, at a frequency of 0.30657, or 72 times.This is a total of 72 records for this bird submitted over the course of at least a decade (the data technically goes back to 1900, but the overwhelming number of records are from the last decade), so this bird might be recorded a half dozen times a year on average. Although this is a reliably seen species in Boston, it is tricky to find and is not often reported. So at around 200 species, things begin to get complicated, as the number of records is low enough that unusual data starts to appear. For example, the Grasshopper Sparrow is listed in Fisher and Benzener as ‘Extremely Rare’ and, indeed, prior to 2015 the species was ranked #265 on the Suffolk County Target List (and was not reported at all in 2010, 2011, or 2012). However, an individual appeared over the winter at the Boston Nature Center and the large number of birders who visited to add the bird to their ‘life list’ caused the bird to shoot up 55 spaces in the rankings to #211 as of this writing, very nearly as frequently reported as the Bay-breasted Warbler, a bird that is seen every year. One individual seen by many people resulted in the appearance of this bird in the mix with species that are known to be regularly occurring in Boston.
So, although the data from eBird for Suffolk County is a reliable record of the number of species regularly seen in Boston, caution must be taken with the data in the bottom third of the list, as it can be easily thrown out of whack by the arrival of one individual “rarity.” It seems like a good idea to treat all records of birds from about number 200 down to number 346 very carefully.
*****
At this point it seems appropriate to divulge that I have submitted slightly under 700 lists for Suffolk County to eBird and have recorded 209 species, including the Bay-breasted Warbler. As I have reached what I think of as the limit of birds for which there is reliable data and I would like to be able to estimate how many species are left that I can reasonably expect to see in Boston, the question of what is a “regularly occurring” species is one that interests me greatly and I spend a good deal of time mulling it over. Studying the eBird data, I know that there are a number of species that I have yet to see that are regularly occurring, such as the Prairie Warbler at #179, a bird I have seen just over the border in adjacent Norfolk County and one I know is here in Boston, but one that I have not yet made a serious effort to find. I must be careful however, not to spend lots of time trying to find certain species. For instance, #210 on the Suffolk County list is the Red-headed Woodpecker, another bird that benefited from an individual appearance in a prominent location (an oak tree directly across from the Museum of Fine Arts in the winter of 2012-2013, and incidentally, a bird I did happen to see). #211 for Suffolk County is the aforementioned Grasshopper Sparrow, a bird I have seen only in California. These are interesting birds, but I am not sure they are worth pursuing. What I mean by this is that I do not really believe these birds are truly ‘Boston Birds,’ and to show up at a location at which an individual has been found solely to add the bird to a life list seems a superficial exercise (I know there are those who might argue that birding in general is a superficial exercise, but I disagree). Tracking down individual birds that have appeared essentially at random in an area strikes me as bordering on obsessive. If a bird is meant to be in a ‘patch’, it strikes me as fun and enjoyable to try to meet it in the place it is meant to be at the time it is meant to be there, much like watching an eclipse or the conjunction of Venus and Jupiter. If a confused Brown Pelican (which is listed as #251 on the target list) ends up in Boston Harbor that is curious but not much more than that. I would much prefer to travel to Charleston and watch the abundant Brown Pelicans there in their natural setting (where they are #13 on the Charleston County Target Species list), while eating a Low Country Boil.
I believe my opinion is in the minority in the birding world, and so feel the need to explain my position. Most birders love accumulating massive life lists for whatever reason (I will refrain from speculating, although I have some theories). Other people merely enjoy seeing a bird and trying to figure out what it is, and have no interest in maintaining any kind of life list. I enjoy seeing birds where they are expected to be found, when they are expected to found. I like birds to be in their ‘normal’ environment because if they are new to me, then the environment will also likely be novel for me, and this interests me more than seeing a bird in a place it does not belong that was found by somebody else.
One counterargument that to me has merit is the notion that many birds are naturally vagrant; that is, they somewhat reliably wander off course for one reason or another. The study of vagrancy is a fascinating topic and I know that at least one of the ‘top’ birders in Suffolk County is deeply interested in the science of vagrancy. An unusual appearance by an individual in Suffolk County is data in this case for a scientific endeavor, and that seems fine to me, particularly as I am a big fan of the “treasure your exceptions” school of scientific inquiry.
What I am rambling about here however, is a distinction between ‘ticking’ birds merely to create a large personal “life list” and looking for birds that are reasonably expected to be seen in their ‘natural’ environment. I get very little pleasure from showing up at a site, Forest Hills Cemetery for example, with dozens of other birders merely to look at a bird, a Black-backed Woodpecker for example, that somebody else found in a place it was not meant to be. On the other hand, if a Black-backed Woodpecker wants to pop up in the woods at Franklin Park unexpectedly while I am walking my dog (which actually happened to me this winter!), I have no problem with that. I will dutifully record its presence, alert those who wish to add it to their life list, and happily enjoy the pleasure of watching a bird that I would normally have to travel hundreds of miles north to see. However, I would prefer seeing a Black-backed Woodpecker in its natural home in the forests of Quebec. To me the difference between these two types of birding is comparable to either drinking straight ethanol out of a flask because, after all, alcohol is meant to make you drunk, or eating a long meal consisting of many courses each accompanied by wines that complement the superb food. You might end up drunk and happy both ways, but I much prefer the latter to the former.
*****
I once was asked by some students of mine why I birded. My answer was that I would very much like to be a tiger watcher, but that is a much more difficult enterprise likely to end in failure, whereas wherever one goes, there are always birds to see. If a tiger comes along while I am looking at birds in India, great! But If I went to India looking specifically for tigers and ended up seeing only birds I would be disappointed. There is a cliche about the lottery that “you can’t win if you don’t play.” I feel that by birding I am ‘playing’ but even if I don’t hit the ‘jackpot’, I will still win back my stake and more and I still have the possibility of winning the big prize.
Which leads me to another admittedly eccentric reason I like birding: it gives me a method to maintain a record of the places I have been and the things I have seen. There are about 10,000 avian species in the world, and I have recorded 770 species in the 12 years or so that I have been submitting lists to eBird (I birded before this time but one of the positive personal developments of reporting to eBird is that I take my lists much more seriously so the quality of my lists has improved. I have less faith in the data I collected prior to 2003 as it was not collected as rigorously, so I have not submitted much of it to eBird). This modest number is about 8% of the bird species to be seen in the world. Since birds are found all over the planet, I like to think that means I have seen about 8% of the world. It gives me a concrete number to assess how much I have seen as well as how much I have not seen. This type of data also allows me to plan trips with an eye to seeing the maximum number of new species. In my view this is akin to visiting the place I know the least about, as the birds are totally new so the ecosystem will be new, and the culture will also likely be new.
Also, when I return to places I have previously visited, I bring a list of ‘target species’ I have not seen, which supplements my list of all the birds one can see, so that I can focus in particular on species I have yet to see, in much the same way that I might visit the Cooper Hewitt Museum in New York for the first time because I visited the Metropolitan Museum and other museums on previous visits. Sometimes these species require me to go to an area with which I am unfamiliar and so I expand my knowledge of the natural areas of New York, to continue with the current example.
A couple of years ago, I walked the Camino de Santiago, an ancient pilgrimage route that crosses Spain from the Pyrenees in the northeast to the Cathedral City of Santiago de Compostela in Galicia in the far northwest of the Iberian peninsula. This walk of about 800 kilometers (500 miles) crosses diverse terrain, including the mountains of Leon and Navarre, the fertile valleys of La Rioja, the open and flat Meseta of Castille, and the lush, rainy forests of Galicia. I brought my binoculars and birded as I walked. In the end I recorded over 100 species, most of which I had never seen before. Approximately 470 species have been reported in Spain on eBird, about 400 of which have been more than three records. Thus, I have seen at least a quarter of all the birds I could reasonably expect to see in Spain. I walked across the entire Northern region of Spain and subsequently visited Madrid and Andalucia, so the idea that I saw about a quarter of Spain is not as far fetched as it sounds.
I plan to visit India for the first time next year. According to eBird, 1180 species have been reported in the country. Of these I have seen 164 of these species (which will be great fun to see again) on trips to other places in Asia, leaving 1016 new species for me to discover in India. This is fully 10% of the known species on the planet. As early as 2022, India will become the largest country in the World, with about 17% of the world’s human population. If I see 100 species, it will give me a sense of accomplishment; perhaps I will not see exactly 10% of India, but I will have been to India, and I will have a record of the times and places I saw individual species, which will remind me of the meals I ate and the people I met and the things I saw. There is a symmetry between the birds and the cultures of the places I visit that I enjoy thinking about. I can pretty much be guaranteed of seeing the Red-vented Bulbul, my number one target bird for India, perhaps even in the Red Fort in Delhi, but certainly somewhere in India. I will certainly always remember where I saw that bird for the first time, as I will always remember our first meal there and the places we visit. I will forever associate certain birds with certain places, certain people I met in those places, and certain meals I ate in those places.
Plus there might be tigers!
UPDATE: May 8, 2016. I am now back from India. 144 Species seen, including 108 birds new to my lists (Life birds, as they are called in the birding world). Alas, no tigers, but did see a leopard at Panna National Park in Madhya Pradesh, which was very cool, as well as a jungle cat, and many other mammals, amphibians, reptiles, insects, plants and other natural wonders. We also had an amazing cultural experience, albeit somewhat tempered by the omnipresent poverty and abundant pollution. As I said in this essay, I may not have ‘seen’ 10% of India, but I have seen a chunk of it and it surpassed my expectations. Now when I peruse my lists and see Egyptian Vulture, for instance, it will bring back memories of the Taj Mahal, while Indian Rollers will remind me of the countryside in Madhya Pradesh. I did in fact see a Red-vented Bulbul (16 times in fact), but not at the Red Fort. I still very much enjoyed the Red Fort.