Legally Blind Birding

Testing the Patience of Birding Guides Around the World

Retinitis Pigmentosa, or RP, is a degenerative, hereditary eye disease, and a miserable hand to draw at the table of genetic inheritance.

RP reduces, or outright destroys, peripheral vision, by attacking the rod photoreceptors which are distributed to the sides of the retina, away from the back of the eye, where the cones predominate. The cones provide detail, acuity and color perception, but they are limited to the center of the visual field. So the RP victim typically experiences tunnel vision, though in some cases it compromises the cones too, resulting in total blindness.

The rod cells that populate the outlying regions of the retina also provide night vision – a fact known to every amateur astronomer, for it makes possible the trick of averted vision: while looking at a particularly faint object, you are advised to direct your eye askew, letting the faint light of a distant galaxy of diffuse nebula fall upon the rods on the side of the eye. And indeed, what was only a faint smudge before will become a slightly brighter, more detailed smudge. With RP the rods don’t function, so low-light conditions are no-light conditions.

One might think that tunnel vision implies a view of blackness punctuated by a small aperture of visibility, like this:

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Anyone in there?

This is not accurate. There isn’t any black. To see the black of the tunnel walls would be to see somethingThere just isn’t anything to see beyond the central core. And the brain isn’t content with the lack of information from the eyes, so it fills in. Sight is a joint effort of optics and image processing that builds a view of the external. In my experience, a better representation, though not perfect, is more like this:

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Different. Not better.

In neither case can you discern the Many-colored Rush-tyrant to the lower right of the area of interest:

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This is a photo I took during a trip to Argentina. I was having so much difficulty finding this little guy that I put the bins down and just starting taking photos in the general area where the guide pointed. Sometimes that is the only way to ‘see’ a bird.

The ruse makes it seem that the tunnel isn’t there. And if nothing happens or changes in the visual periphery, then the illusion is good. It’s as if you see everything. You can walk through your house, the details of which are well-known to your brain, without incident. But should the cat decide to crouch on the floor, the cat will be trod upon. Cats eventually learn to alter their behavior in a house with a blind person.

More difficult to navigate are public areas with people moving about without constraint, such as a busy airport. You seem to see everything, but then suddenly, a body materializes, as if beamed there by the fastest of teleporters, so close that a collision is barely (or not) avoided. It is startling, sometimes embarrassing, and potentially dangerous. (Airports are hell, as they are the natural habitat of rollerbags, those dreadful trailing extensions invariably in the no-sight zone. To those of us with reduced vision, they are a damned scourge.)

But the greatest frustrations for a birder involve birds, of course. We once attended something called “Jaegerfest” in Superior, Wisconsin. It was not a good experience. A ceaseless and hellish October wind came pouring off the Great Lake, watering the eyes and freezing the tears, while thousands of unidentifiable distant gulls wheeled in the poor light. From the assembled line of scope-wielding birders came the occasional cry of “Jaeger!” and instructions to look “at two o’clock, above of the water tower” or something similar. That anyone could then pick out one bird from that swarm was quite impressive, but beyond my abilities, so we left.

A nearby small lake provided a respite from the wind, and the waterfowl took advantage. Pintail, Green-winged Teal, Canvasback – amazing how they rode the waves on that blustery day in such a tight group, even as a man in chest waders clambered out towards them… what an idiot I am. I had trained my scope on this while a few bemused locals snickered behind me about the nice mixed flock of decoys I was studying.

We went back to Lake Superior, in time for the excitement of a Sabine’s Gull flying directly towards the shore, mixed among the copious and less interesting gulls. With RP, finding the unique gull flying amidst hundreds of others is no easier than finding a Greenlet up in the canopy. According to those around me, that Sabine’s Gull flew within tens of meters of the shore, banked, displayed its signature pied wing pattern in a most edifying and satisfactory manner, and then departed. I never saw it. The fellow next to me observed aloud that “No one can complain about that! What a great view!” Well I could have complained.

I used to keep my vision problems to myself, unwilling to be treated differently. But after the disbelieving guffaws of more than one guide and declarations such as “What? It’s right in front of you! How can you not see it?!” I decided to tell all my guides up front that I had a disability. Good guides account for this and remember, but others… not so much. After explaining my situation (in Spanish, no less) to a guide in the Ecuadorian Amazon, he was soon shouting at me, “Look with your binoculars! Look with your binoculars!” when a skittish Rusty-belted Tapaculo was moving below some nearby leaves in a very dark forest. As if that would have helped. I was lucky to have seen a flash of it with my unaided eyes.

Testing The Patience of Birding Guides Around the World – that’s my motto. Happily, most of them do a fine job, and more often than not I get the bird, because I’ve learned to be content if I get a recording of their call or song. However, I’ve been tempted to bring along some hardware that others can try on to see what it is like to bird in the tunnel:

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Want to know what it is like to bird with RP? Get a Tusken Raider mask!

 

The recent accomplishments of Noah Stryker and Arjan Dwarshuis are impressive. Anyone that has traveled internationally for birding understands how grueling even a week or two can be. Uncomfortable overnight flights, jet-lag, immigration and visa paperwork, often barely adequate rooms (some with six- or eight-legged visitors), extreme heat, humidity or cold, and the joy of traveler’s diarrhea…would you endure any of this without the reward of seeing some spectacular birds? An entire year would be punishing indeed.

In spite of this, twelve months in worldwide pursuit of birds is a prospect that many of us would jump at. Not necessarily for the purpose of breaking what will be an increasingly formidable record – as gratifying as that would be. If that is one’s goal, the sooner done the better… as the record is broken again over time, it will reach a natural asymptotic limit, becoming more and more difficult to exceed. (Predicting this number is an interesting statistical question, which I plan to address later.)

The prospect of simply having an unencumbered year in which to bird is very seductive. For many of us, the necessity of attending to our day jobs renders such a extended project impossible. So what would be some next-best scenarios for attempting a ‘record’?

All birding contests, or anything that can be quantified with a record, must feature some kind of constraint. Even for a global big year, we have the arbitrary conditions of starting and stopping at a January 1st boundary. Big Year competitions based in North America feature geographical limitations based on arbitrary boundaries. A more recent, novel constraint is the ‘Green’ Big Year, which involves avoiding the use of fossil-fuels during travel.

A benefit to restricting a tally to a region such as North America is that it renders it possible to bird competitively through the year without having to abandon work – given the smaller area to cover and a total count expected to stay under 800 or so birds. What about a different tack? Let’s propose a contest that recognizes the biggest limitation that most of us have – the lack of free time. Let’s have a global big year for working stiffs category: a Global Big Working Year (GBWY), or a better name, if you’ve got one.

The rules might run as follows:

You have 365 days to tally your count, starting on Jan 1st. During that time, you must be working, or pretending to work, or otherwise not birding, for a minimum of 40 hours per week. You are free to bird on working days; before work, after work, over lunch or from your office window, but no more. Weekends and vacation days, of course, can feature as much birding as you can fit in, with no restrictions on geographical location.

Vacation time – how much time should be allowed? We can attempt a reasonable answer by looking at typical leave time around the world.

Based on this accounting, the median number of days off is 28. Combined with weekends, we come to 132 days that could be used fully for birding, and 233 days in which birding can only occur in concert with a normal, eight hour-per-day work schedule. If you have to burn a vacation day as part of your travel, then that counts against your allotment of 132 days, unless your travel is part of your work. (I checked with your bosses, and that’s what they said.)

Not everyone gets the same number of vacation days, so an adjusted total could be determined at the conclusion. The adjustment would increase your ‘score’ if you had less than 132 days free for birding. For example, if you had only 120 days of full birding due to work demands, and you recorded a total of 1,200 species, your adjusted score would be 1,320, which simply extrapolates your 10 bird/day average out to 132 days. (We need to put some lower limit on this, otherwise we could theoretically bird just one day, record 100 species, and then achieve a score of 13,200! A natural choice would involve the case of the poor sod that gets no vacation, leaving just 104 weekend days.)

So, if you used V vacation days and counted a total of N species, the adjusted score would be:

N * 132 / (104 + V)

How many birds could one expect to see under these conditions, assuming you could accumulate species at a comparable rate as the world record holders? In one year, Noah Stryker recorded 6,042 species based on Clements taxonomy (10,550 total), while Arjan Dwarshuis recorded 6,852 species using the IOC taxonomy (total of 10,672). Normalizing the Dwarshuis number for the Clements taxonomy, the value is 6,774, and that works out to between 18 and 19 species a day… 132 days of birding at this rate nets some 2,443 species. Adding the part-time birding that one can do during work days, a goal of 2,500 species, roughly one quarter of the birds on the planet, does not appear unattainable.

It is possible that this number has already been reached, but lacking a formal category for recognizing it, it won’t be widely known. If you’ve done such a GBWY, please leave a comment or a note. Such a category would appeal to many birders, and if we can have such as thing as a naked birding life list, then why not this?