SOME FALL MIGRANTS & WHY I SHOT APERTURE PRIORITY

This is going to be a twofer post – one post, two related topics:

• Some shots of some of the neotropical migrants I took during the pandemic Falls of 2020 and 2021 and why my Olympus kit’s mobility is integral to my Fall migration birding preferences. Integral to the getting the shot and keeping it fun.

• Why I chose to shoot in Aperture priority during the typical session of chasing and attempting to capture images of these tiny bundles of constant jitteriness and movement. While keeping the fun factor up and profanity to a minimum.

Fall Migrant (Most All Small Songbirds) Challenge

I’m defining neotropical migratory birds as birds that are Western Hemisphere species in which the majority of individuals breeds north of the Tropic of Cancer (the northern most extent of the tropics) and winters south of that same latitude. The ones that we see most here in inland Georgia are songbirds such as: Warblers, Thrushes, Tanagers, Vireos. Although, there are many raptors, including hawks and vultures, that migrate through our state. The problem for me is knowing which are residents and which are migrants. Along our coast, especially our beautiful and protected barrier islands, there are many species of shorebirds, but I didn’t venture to the coast during the last two Falls. So the shots for this post are the songbirds that visited our yard or our neighborhood nature preserve.

The majority of these birds migrate at night and rest and refuel during the day. The warblers and vireos primarily dine on insects. Many forage at different levels in the canopy (different species prefer different levels thus ‘sharing’ a bug-loaded tree) and glean arthropods of all types from the leaves and bark. This is the reason birders talk about getting ‘warblers neck’. Some forage and eat bugs in the understory. Either strategy keeps them on the move between trees and shrubs and along limbs.

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

They are never still. My strategy is not to be still either. I move, slowly and deliberately, looking for their movement. Sometimes they will be in mixed flocks with chickadees and titmice and these two’s nosiness will give them away. When I find them, I work the shot, i.e., shoot tons of shots, to try and get that fleeting moment when the target is in the open and kind of posing. All shots are handheld. Many are looking overhead.

This ‘run (actually walk stealthily) & gun’ mobility tactic is possible because of the size (even now with the huge M150-400 F4 TC) and ergonomics of my Olympus kit. As I explain here.

Why Aperture Priority

I’ll start with two personal points-of-view that lead me to this decision:

• Exposure and noise control is about getting as much light (as many photons) on the sensor as possible. While managing the depth-of-field and desired motion blur
• I want my limited cognitive capacity dealing most with what’s in front of the lens and less fiddling with camera stuff

Exposure is f-ratio + shutter speed. For a given f-ration, once the shutter closes you have captured all the light – good photons and bad, random photons, i.e., noise – you are going to capture. From that point on, everything, including ISO, is about brightening or darkening that exposure.

Combining my two points of view, I have two of my Custom Modes (C4 & C3) set to Aperture Priority set to wide-open (on my Pro lenses). This means that I have maximized one side of the Exposure equation and I don’t have to think about it. The camera decides the ‘fastest’ shutter speed to give me the ‘correct’ exposure, i.e., a center-average at middle gray. Because this is an ‘automated’, not manual, mode, the camera’s decision of shutter speed is dependent on the ISO setting. In these two Custom Modes, I have preset the ISO to 800. This is based on experience that in a forest setting I will very often get a close to satisfactory shutter speed. By satisfactory, I mean slow enough to maximize light input, but fast enough to rely on the superb stability of the kit to eliminate camera-shake blur. My concession to doing some thinking about the camera is because with these birds movement blur is always a possibility so I don’t hesitate to use the ISO button to bump the ISO to 1600 or even 3200. I’m also a big user of Exposure Compensation. I have it on the front button so I can quickly adjust with my index finger. I have on the ‘blinkies’ and will add as much compensation as I can (slow the shutter speed) until the ‘blinkies’ start flashing or the shutter speed falls too close to my comfort level, which is around 1\160 or so. It is very important to note, without getting into the weeds, that the EM1.3 and EM1X are near ISO invariant, especially at 800 and 1600. This means that I can adjust image brightness up or down in Lightroom CC Classic without a noticeable penalty in image quality. This fits with getting the most photons I can when taking the image, but relying on post processing to adjust brightness.

In the paragraph above about mobility being critical to this birding tactic I included ergonomics. The reason is because I can make these adjustments to the shutter speed side of the equation without taking my eyes off the target in the EVF.

Earlier I mentioned I had two Custom Modes (C4 & C3) set to Aperture Priority. The differences are: In C4 autofocus is SAF and single eshutter, C3 is CAF and low burst eshutter. C4 is for the few times that I think the bird(s) will perch. C3 is for when I’m sure they won’t. Both have the smallest focus box centered. This is because for both I’m trying to thread the focus through the smallest gaps in the leaves and limbs.

• 

• 

• 

• 

• 

• 

There are many threats to neotropical migratory birds. Of the 341 species, 127 are known to be in decline. Sixty species are in
severe decline (population decrease of 45% or more in the past 40 years), of which 29 are songbird species.

The culprits are the same old cast of characters: Fragmentation of breeding, staging, and wintering habitats due to development, land
conversion, habitat degradation, and deforestation, collisions with buildings and communication towers, poisoning by toxic chemicals such as pesticides, predation by introduced predators, and global climate change.

There is good news. The Neotropical Migratory Bird Conservation Act (NMBCA), passed in 2000: “The purpose of the Neotropical Migratory Bird Conservation Act is to provide financial support and foster international cooperation for initiatives that will perpetuate healthy bird populations.”

Between 2002 and 2020, the NMBCA has funded $75M in grants that have been matched by $286M. This money has been invested in 628 projects in 36 countries have positively impacted 5 million acres.

And in even better news, on October 4th the U.S. Fish & Wildlife Service “published the final rule revoking the January 7, 2021, regulation that limited the scope of the Migratory Bird Treaty Act. With this final and formal revocation of the January 7 rule, the Service returns to implementing the MBTA as prohibiting incidental take and applying enforcement discretion, consistent with judicial precedent and long-standing agency practice prior to 2017. This final rule goes into effect on December 3, 2021.” https://www.fws.gov/regulations/mbta/

Threats still exist, but positive things are happening to protect these high energy gems. And, the opportunies to take up the challenge of getting a decent shot of them.