In life and death

Whenever a bird dies at the wild bird center from unknown circumstances we try to do a necropsy. A necropsy is basically a post-mortem examination on a non-human animal. Just like an autopsy, but again, not on a human. I started doing necropsies on deceased patients when I was an intern at the Florida Keys Wild Bird Center in Tavernier in 1994. My mentor at the time, Laura Quinn, thought that these experiences were crucial for wanna be rehabilitators and was always annoyed with the interns that baulked at the idea! When a patient would die, and if time allowed, we would perform the procedure out back behind the hospital that housed the intensive care patients. Laura had a table set aside for the task and all the tools she would need. In the "olden days" we used to spend 20 or so minutes prepping the bird carcass for the necropsy by plucking its chest feathers so we could have access to the skin. If you cut through the feathers with shears they tend to fly everywhere! Later, I learned a much, much easier prep technique while attending a necropsy workshop at a wildlife rehabilitation conference. Simply spray lots and lots of rubbing alcohol on the bird's chest and the feathers become matted rather than flighted. A lot of the species we work on are either water resistant or waterproof. Using water doesn't do a dang thing! However, the oil or powder that the birds' use to accomplish their water resistance are no match for rubbing alcohol.

When doing a necropsy with Laura it wasn't an exact science. She would open up the carcass and point out the vital organs. Sometimes they would be healthy looking and, after a number of these necropsies, it wasn't hard to recognize unhealthy tissue. When I participated in the conference workshop I learned a few more techniques. Namely a necropsy should always be performed in the same manner...A to Z. I exclusively rehabilitate birds and therefore have only done less than a half a dozen necropsies on mammals. These were usually done with a volunteer veterinarian because their insides do look different than birds and if you don't know what you're looking at the procedure is basically pointless. The A to Z manner starts with always placing your specimen in the same position. This makes it easier to recognize "where you're at". The first step is to examine the bird externally before you even begin to dissect it. For example, check feather condition and around all the orfices for blood, clumped fecal matter, oozing, etc. I look inside the mouth and ruffle feathers looking for parasites such as lice and mites, too. After the feathers are matted with the alcohol I use a sharp scalpel and strip away the skin that covers the chest. I examine the muscles underneath for things like bruising and more parasites. Once the carcass is completely open I usually start at the top. I look to see if the bird had any body fat, the color of the tissues, or any lacerations such as a torn liver. I check that the lungs are a healthy neon pink. If they are pale, the bird may have suffocated. If they are gray or greenish, the bird may have inhaled water. Blood in the lungs from a collision is also pretty obvious. I look at the organs. Do they all seem to be what I'd consider normal in size? Is there fluid or fat around the heart? A huge bag of fluid around the heart could mean that the bird died from heart failure. I check the inside of the trachea for plaque. I've never seen it inside a bird, but once witnessed the necropsy of a sea turtle and was told by a world renowned veterinarian that what I was looking at was considered pneumonia. I check the contents of the stomach and push things around (or remove them if need be) to take a look at the kidneys and other organs that may be hiding behind the liver. Birds have the unique ability to shrink their sexual organs to 1/18th the size they need them to breed with when not in breeding mode. I have learned that the older the bird is the easier it is to even find these itty bitty organs. Testes for males and a cluster of eggs (which looks like itty bitty grapes) for females. I have even necropsied an adult pelican before and simply was unable to find its sexual organs at all!

There's a lot to be learned from necropsies and I try to do them with interested interns and volunteers at my own facility. Some say, "No thanks," while most say, "Cool!" The experience is fascinating and not something that makes most people squeamish. I will admit that I will probably never be witness to a human autopsy because I have found that even watching fake ones on TV, like on CSI, does make ME queasy! More often than not the results of a necropsy does provide us insight as to why the animal died and this makes the time it takes us to do it even that more valuable.

The other morning we found one of mature permanent double-crested cormorant dead in our main flight pen. It happens. Some of these birds are old and have to die, that's part of "Life and death". However, we couldn't help wonder if that was the cause and took the time to do a necropsy. I was lucky enough to have on hand an intern, Rob Qually, who aspires to be a zookeeper. Together we went through the A to Z procedure. When we opened the carcass I was able to point out to Rob that what we were seeing was definitely not normal! The lungs were oddly dark, the bird was large but had no body fat and it's liver was not the normal maroon color it should have been. Also, right way, we could see that the stomach was full yet hard and distended. We opened the stomach and were shocked to see its contents. A tight clump of feather shafts! We removed the cluster and counted 30 feather shafts and two twigs about the same length of the feathers. I had never seen anything like it! Apparently this cormie had an eating disorder. His craving for feathers had obstructed food which explained his lack of body fat. The impaction most likely led to organ failure, hence the discolored lungs and liver. Behind the liver we also observed discolored kidneys. The cause of death appeared to be a disease known as Pica,

a medical disorder characterized by an appetite for substances largely non-nutritive. Who would have thought a bird, specifically a double-crested cormorant, could have such a thing?!

We also had on hand a new patient that had come in the night before. A laughing gull that Rob had rescued from a local beach. The caller had described to me a gull that wouldn't fly away and was drooping a wing. Rob had said that he had not observed the bird drooping its wing when he rescued it. It had died during its first night in the hospital. The bird was emaciated, having no visible body fat. This time, however, the tissues and organs were of normal color. I mentioned to Rob we should investigate the shoulder areas as, like I said, the caller had said the bird had been drooping a wing. We peeled back more tissue to reveal the shoulder area. Here we found something. A lot of necrotic (dead) tissue. Necrotic tissue is black and dry. As we continued to cut into the necrotic tissue I saw something unusual. Within a moment we had a cause of death. I easily extracted a two inch fish hook from the necrotic tissue. The hook had obviously snagged on the bird quite some time ago and had worked its way into the bird's body, namely the shoulder joint. The cause of death was starvation due to the bird's inability to fly to places where it could find sufficient food.

Necropsies may sound like an unpleasant procedure but can reward those who do them with vast knowledge. I have probably done at least 500 necropsies and it not only helps me to identify causes of death, but as Laura Quinn originally explained to me, helps me to also understand how the body works when it's alive. I know where the organs are and this allows me to make educated guesses as to how to better help a bird if it sustains an injury in a particular area. For example, if a bird has a hook in its chest, close to where the heart is, the hook may have penetrated the heart. I would want to x-ray the bird to confirm this prior to attempting to simply remove the foreign object. Also, internal injuries, such as a bleeding liver, may be the case if a bird hit a powerline and sports a bald spot on its abdomen in that vicinity. Bed rest before exam could mean life or death for this patient. And by the way, the size of Rob's eyes when we came up with two conclusive causes of death told me that he thinks necropsies are "Cool!" not "Gross!".