Alberta Golden Eagles Part II by Jon Groves

Alberta golden eagle nesting pair. Note the deer fawn leg and mallard remains on the nest.

Alberta golden eagle nesting pair. Note the deer fawn leg and mallard remains on the nest.

In early July the two eaglets were banded, an older male and younger female. This was the first year where this nesting pair produced two young, food resources were likely plentiful. A week after banding I went out to check the nest and couldn't see either eaglet on the nest or in the area. I was alarmed because the eaglets were still mostly down-covered and incapable of flight. Furthermore, there were no visible prey remains in the nest so I assumed a feline predator managed to climb in and raid the nest. The nest was normally littered with prey remains and the smell of decaying mallards and deer baking in the summer heat would surely attract predators and scavengers. There aren't many mammalian predators capable of accessing this cliff nest and they certainly aren't common in this area of Alberta but I immediately blamed a bobcat or cougar for wiping out the young.

I couldn't see anything from the cliff top so I decided to hike up the river and have a look under the nest. I was relieved to see both eaglets sitting below the cliff along the river bank trying to find some shade. There is a possibility something spooked them off the nest at night but it seems more likely that the young bailed off the nest to escape the summer heat. The nest location offered no shade during the heat of the day and the young were large enough where the female couldn't efficiently provide shade for them anymore. In addition to the eaglet's increasing size, their food demands were also rising substantially and both adult eagles were hunting now to meet the demand.  The young male eagle was much more mobile at this point than his larger more cumbersome sister but it was clear by the visible prey remains that the eaglets were still being fed in situ by the adults. The adults were rarely seen around the nest at this stage of the nesting cycle and they both spent considerable time hunting, often cooperatively. I managed to witness two successful hunting flights at ravens. Ravens are extremely aerial and adroit on the wing but it seems they aren't much of a match for a pair of hungry golden eagles. 

The eagles were out below the nest for almost two weeks when a massive storm system passed through the area dropping almost five inches of rain in 24 hours. The day after the deluge of rain I hiked up the valley to check how the eagles were faring. I first noticed how much the river had risen as I approached the nesting territory, it was also loaded with silt and sediment from the tremendous runoff in the area. Because the cliffs and banks in the river valley are predominately clay and exposed soil, they are much more prone to erosion than rocky outcroppings. As I rounded a bend in the river I could see the young male perched in his usual spot but I couldn't see the female. I could see a massive soil slump near the area where the eaglets had been hanging out, and the slump was so large it blocked the entire channel and this explained the high water level I noticed when I hiked in from the upstream side. When I got closer I could see the body of the female eagle among the soil and debris that slid into the river so I swam across to retrieve her. The female eaglet had a large contusion on the back of her head and must have been struck when the soil came cascading down the cliff during the heavy rain. Raptors often succumb to vehicle collisions, electrocution, and colliding with man-made objects but it was a natural occurrence that killed the young female eagle brought on by rare stochastic weather event. More rain was received in 24 hours than the whole month of July on average. The pair of eagles managed to successfully fledge the young male and he was seen with the adults as late as October. 

Adult female golden eagle with two eaglets on the nest. The younger but larger female eaglet showing far less feather development than the older male in the background. 

Adult female golden eagle with two eaglets on the nest. The younger but larger female eaglet showing far less feather development than the older male in the background. 


Ethics of Feeding Wildlife for Photography by Jon Groves

The topic of feeding wildlife has been an active on social media that often leads to heated discussion. I’ve never been one to dive into such topics because voicing an opinion on this matter in attempt to sway the view of another is largely and exercise of futility. I’ve decided to write a short opinion piece on this topic based on my own experience with wild raptor photography.

Snowy owl

Snowy owl

Even those not particularly interested in natural history are enamored by raptors. Much of the online rhetoric among nature photographers inevitably arrives at the controversial subject of feeding raptors for photographic purposes. Most call the practice "baiting" and I’ve heard all sorts of reasons for why it shouldn’t be practiced. Here is a short list of the more common arguments against "baiting" that I've heard:

-Habituation where the raptor loses its hunting instinct - This is an illogical argument. Instinct is an inherent behavior. When a raptor is fed by a human it doesn't forget how to hunt or eat. Just like a songbird doesn't forget how to forage for food after the feeder is empty.

-Increased risk of road-traffic mortality in habituated raptors - Raptor mortality due collisions with anthropogenic sources occurs regardless of supplemental feeding. I cannot see how feeding increases risk of mortality on a population scale.

-Causing general undue stress to the raptor - How is this measured? I would argue that photographers constantly flushing birds trying to get close for a photograph cause more stress.

-Feeding an owl mice causes disease in raptors - rodents are by far the safest food for a raptor, I'm not aware of any transmittable diseases from a mouse to a raptor through consumption.

None of these arguments against feeding raptors are supported by evidence and you'll often hear anecdotes about an owl that suffered somewhere because of feeding by photographers. Like most contentious subjects, arguments against are emotionally charged. I feel the majority of those outspoken photographers against feeding raptors for photography see it as cheating, selfishly loading the dice to take a "better" photograph. Most will never state this as their reason and will instead regale you with tales about stressed and dying owls as a result of feeding mice. I understand the logic that attracting raptors with food for the purposes of photography is a contrived and unnatural situation...I can comprehend why there are wildlife photographers not interested in the practice for this reason alone. Like other photographers, I appreciate the rewarding experience that comes from taking a wildlife photograph without the use of a food attractant to stack the deck in my favor. But please avoid taking an emotional position based on conjecture by saying the raptor can be harmed in some way through feeding. Those against the practice of "baiting" will call it unethical. Ethics are a matter of personal opinion and each person's moral compass is different. It's a slippery slope when it comes to ethics and nature photography, some ultra-purists will even frown upon photographing habituated wildlife in parks and sanctuaries. The "anti-baiting" sentiment is amplified further by the sort of photographs that would be impossible to take without a food attractant - this breeds anger and resentment fueled by jealousy in those who don't support the practice.

Interestingly, many vocal opponents have no problem feeding songbirds at a feeder for the purposes of photography or observation. Passerines are generally granivorous and raptors are obligate carnivores, I see this as the only difference but I derive my opinion from years of handling raptors through the sport of falconry, rehabilitation, and bird banding research. Many don’t realize that bird feeding has numerous detrimental effects in spite of its growing popularity. Studies have shown that using a feeder for songbirds causes them to congregate unnaturally with increased risk to diseases such as avian pox and trichomoniasis. Some will argue that bird feeding is beneficial through increasing survival, especially during winter when food resources are limited. Why is it any different for a raptor? I don't believe it is, but a very vocal group strongly opposes feeding raptors yet they’ll feed chickadees out of their hand all day long and not bat an eye. You'll rarely (maybe never) read any online discussion surrounding the "baiting" of a hummingbird with nectar and a flower setup for photography, this has always perplexed me.

On a personal note I’ve worked closely with raptors since I was a teenager and developed much of opinion based on the experience I’ve gained with handling the birds through falconry, rehabilitation, and bird banding activities. I am an ardent conservationist interested in natural history and ecology well before taking up nature photography and I have yet to see an example where feeding wild raptors results in any negative effect to the birds. I will also argue that some food-stressed raptors during winter can benefit substantially from supplemental feeding. With all the risks wild raptors face due to human activity, feeding raptors shouldn’t be something warranting much discussion in my opinion. Based on cumulative threats of habitat loss and fragmentation, combined with the increasing human footprint, we should be more concerned with actions that actually cause population declines in raptors. If I knew that feeding raptors caused negative consequences I wouldn’t do it, I have too much appreciation and interest in the birds to be comfortable with the potential stress or demise of an individual for my own selfish interest in taking another photograph.

 

Alberta Golden Eagles Part I: by Jon Groves

Female golden eagle bringing in some green nest material

Female golden eagle bringing in some green nest material

This past summer I spent considerable time observing and photographing a nesting pair of golden eagles in southern Alberta. These golden eagles nest in the Rosebud River valley as it carves through a landscape dominated by cultivation, alternating between cliff and tree nest locations in some years. These eagles are unique because golden eagles are typically found at a relatively low densities in ideal habitat and normally absent from areas heavily disturbed by modern agriculture or development. My goal with this endeavor wasn't only to get some unique photos of nesting golden eagles but to observe the behavior of the breeding pair. I was particularly interested in what sort of prey they were exploiting and the remote camera was successful in answering some of my queries.

The eagles are year-round residents in the area with courtship activities and nest building initiated in mid-February. For the 2015 breeding season a cliff nest used previously was chosen and the female began incubation on April 1st. Early on I had planned on photographing nesting activities through the use of a remote camera setup that I could trigger from a long distance while observing with a spotting scope from a kilometer away. Golden eagles are particularly sensitive to disturbance near the nest site so it was imperative that a remote camera setup be used.

Female golden eagle incubating on the cliff nest. Female golden eagles will incubate for approximately 45 days while the male delivers prey. Early May 2015.

Female golden eagle incubating on the cliff nest. Female golden eagles will incubate for approximately 45 days while the male delivers prey. Early May 2015.

Through photos and feather collection around the cliff tops at the nest site it was clear that these eagles were primarily killing avian prey, mostly waterfowl. I watched the male eagle bring in numerous mallards and saw him on several hunting sorties while soaring thousands of feet over the river valley. Golden eagles are able to exploit a broad prey base and most studies show that eagles are extremely adaptable to whichever species is abundant in the area. In agricultural landscapes near the Rosebud River mallards are numerous during the spring nesting season and are particularly vulnerable to predation as they wander cultivated fields in newly formed breeding pairs. Because of his colorful spring breeding plumage the drake mallard is at much greater risk compared to the more cryptic hen. The male eagle had a taste for drake mallards but I also observed gull, raven, magpie, and a mule deer fawn brought into the nest.

Note the distinct orange mallard feet among the prey remains. There were at least two ducks in the nest this morning.

Note the distinct orange mallard feet among the prey remains. There were at least two ducks in the nest this morning.

 

During the early brood rearing period the female eagle spends virtually all her time on or in areas immediately surrounding the nest site while the male brings in prey. Because the cliff nest is south facing the female spent much of her time shading her young from the summer heat. This south facing location makes for challenging photography conditions because of the harsh summer light but also from heat diffraction coming off the cliff face. The use of a telephoto lens during these conditions is an exercise of futility with heat waves rendering images painfully blurry. Cloudy days provided for the best photography conditions but we don't seem to get many in sunny southern Alberta. As the young grew to where they could thermoregulate with greater efficiency, the female began to hunt as well, at this point the pair would often hunt cooperatively, no bird is safe when a pair of eagles hunt together.

Pair of golden eagles on the nest. Green vegetation is brought in frequently and is thought to reduce the parasite load in the nest and serve to show that the territory is occupied to competitors passing through the area.

Pair of golden eagles on the nest. Green vegetation is brought in frequently and is thought to reduce the parasite load in the nest and serve to show that the territory is occupied to competitors passing through the area.

Late morning in in mid-June the male eagle was soaring high over the territory while the female sat on a cliff top near the nest. I was watching through a scope from a kilometer away after setting up the camera early in the morning. I hadn't observed any cooperative hunting flights at this point of the breeding season but I was in for a treat this day. As I watched the female in the scope while keeping an eye on the soaring male I noticed the female take off the cliff top and disappear over the bank. I didn't think much of it until I looked up at the male in a full stoop hurtling towards the valley below. I hurriedly grabbed my binoculars to follow the male downwards as he raced towards the earth at breakneck speed. He leveled out and abruptly shot to the side as if fired from a slingshot before merging with a large white bird over the badlands. His prey dodged but the female now showed up chasing in tandem with the male as he used the momentum generated from the first stoop to dive upon the bird again. Initially I thought their quarry was a large gull but I soon determined they were chasing an osprey. This wasn't a nest defense scenario, they were intent on killing the osprey to eat. The osprey managed to dodge both eagles numerous times before escaping into a stand of poplar trees in the valley bottom to avoid the onslaught. It was an incredible show of agility and power that eagles possess, they are an impressive predator capable or air superiority compared to virtually all birds out there, I'd be lying if I said I was cheering for the osprey on this occasion.

Scene of the osprey hunt. The terrified osprey sought sanctuary in the large poplar stand in the valley bottom to live another day.

Scene of the osprey hunt. The terrified osprey sought sanctuary in the large poplar stand in the valley bottom to live another day.