Unnatural Selection: An Interview with the National Fish and Wildlife Forensics Laboratory

Are they blood stains, or rust stains, or fruit stains, or what are they? That is a question which has puzzled many an expert, and why? Because there was no reliable test. Now we have the Sherlock Holmes test, and there will no longer be any difficulty.

—Arthur Conan Doyle, A Study in Scarlet, 1887

Dr. John Watson first meets Sherlock Holmes in a chemistry lab, establishing a connection between sleuthing and scientific analysis that has persisted in the public imagination—as well as in practice. Holmes, the gifted amateur who clutters his drawing room with bubbling test tubes, anticipates the forensic scientist whose study of evidence now forms the foundation of police investigations and successful prosecutions. Science and the law, however, are ever-changing disciplines with differing standards for determining the truth. Caught between the laboratory and the courtroom, forensics becomes as much a task of translation as it is a method of analysis. In 1973, for instance, Congress drew upon the language of taxonomy to pen the Endangered Species Act, which charged the US Fish and Wildlife Service with the protection of endangered animals from poisoning, commercial trade, and other newly defined violations. This law in turn introduced into crime labs a veritable menagerie of new evidence—feathers, claws, hides, and bones. First assigned to a patchwork of forensics labs, zoology departments, and natural history museums, analysis of this evidence has since 1989 been centralized at the National Fish and Wildlife Forensics Laboratory in Ashland, Oregon, the only lab in the world for the investigation of crimes against wildlife. In October 2007, Colby Chamberlain spoke with four members of the lab’s staff—its director Ken Goddard, its deputy director Ed Espinoza, and two members of its morphology department, mammologist Bonnie Yates and ornithologist Pepper Trail.

Cabinet: In 1975, special agent Terry Grosz started petitioning for a US Fish and Wildlife Service crime lab. What brought about the need for such a facility? 


Ken Goddard: At about the time when the Endangered Species Act was put into place, US Fish and Wildlife game management agents were converted over to special agents. They had to act more like investigators or detectives, and less like patrol officers, which had involved checking duck blinds or verifying hunting licenses. Terry Grosz ran the endangered species desk of our Washington office, and he went looking for people to examine the evidence that agents were collecting. He discovered that there wasn’t anybody who could forensically examine wildlife parts-and-products evidence and come up with “species-source” identifications. The FBI Lab couldn’t devote their limited resources to wildlife investigations, and Smithsonian scientists weren’t forensically trained as expert witnesses. Realizing that we had to have our own crime lab, Terry started pounding on desks, pretty much literally, and here we are.

What is the lab’s role in the investigative process? 


KG: Generally we’re involved at the very beginning of the investigation, when the agent has reason to believe a crime has been committed. There may or may not be a suspect; there may just be the wildlife equivalent of a homicide victim, let’s say a dead grizzly bear, a headless walrus, a bunch of dead eagles or parts thereof scattered underneath an electrical pole. They might contact us when they have intercepted a shipment of caviar, shark fins, hides, or furs, and the suspect is unknown. We have a number of agents who work covertly, and we might assist by identifying things those undercover agents purchase while posing as a wildlife dealer. 


Ed Espinoza: That said, we do not do any of the investigative work. We provide information to agents and assist them in a continuing investigation. When we receive evidence for analysis from our agents, their questions tend to fall under three general categories: First of all, what did this thing die of? We have two veterinary pathologists who determine the cause and manner of death of the animal carcasses we receive. Secondly, what is it? Can we tie this feather or bone to the family, class, and order it belongs to? And finally, can we link together the crime scene, the victim, and the suspect? 


I take it, then, that it’s rare that the lab’s scientists are the ones doing the field work? 


KG: Yes, TV shows like CSI do a bit of a disservice to the public understanding of crime scene investigations.They combine a crime scene investigator, a detective, and a forensic scientist into one character. In reality, forensic scientists stay in the laboratory, do not go out to scenes, and let crime scene investigators collect all the evidence. This allows forensic scientists to make far greater use of their time in the laboratory working with the instruments. 


The typical forensics lab might have divisions for ballistics, drug analysis, pathology, etc. What sort of additional divisions does your work require? 


Bonnie Yates: We have all the typical forensics laboratory staff, such as geneticists, firearm examiners, and latent print examiners. What makes our laboratory a bit different is our morphology section. In most crime labs, they’re dealing primarily with one species, Homo sapiens. They may occasionally identify some dog and cat hair, but beyond that they need to seek out specialists in feathers, or specialists in mummified frogs. That’s where our laboratory starts to diverge from a typical police lab. 


KG: In human crime, the species of a dog or a cat usually doesn’t matter, just that there’s dog or cat hair on the scene. That, generally, is all that human forensic scientists or detectives care about. In our case, whether a crime has been committed or not is very much related to the species of the victim. It’s also related to when the victim was killed, what time of day, what week, day of the month. Was it hunting season? On what side of a fence boundary did the shooting occur? What weapon was used? For example, my first case with the US Fish & Wildlife Service was to help determine whether or not a Canada goose had been killed on the Congressional Golf Course by a golf club, because that would have been a crime. I asked them if they expected me to draw a chalk line around a goose lying on a golf green. Having previously worked on homicide investigations, I thought this was a little off-the-wall. They then told me that part of the problem was somebody had run off with the goose. Clearly, I was now involved in a very different type of forensic science. In this regard, I think the morphology section is the enthralling part of our laboratory because we have thousands of pieces and parts: hair, fur, feather, claw, teeth, bone, skulls. The morphology team has to make sense of all that, knowing any evidence could have come from anywhere in the world. That’s a pretty incredible—and difficult—job to ask of our four morphologists. 


Can you tell me a little more about what morphology is and how it relates to your forensics work? 


BY: Morphology is the study of shape and how shape defines an organism. Before coming to the lab, I worked in zooarchaeology, which is the study of animal bones from archaeological sites. In zooarchaeology we use morphology to determine what we’re seeing. For example, you could contrast a paleo-Indian site assemblage with that of white pioneers during the 1800s, so you can see twelve thousand years’ worth of different ways in which animals have been used in the environment. That may seem far away from forensics, but it’s perfectly analogous: you take trace evidence and you reconstruct what happened in the past. 


Pepper Trail: Morphology is a very classic science dating back to the nineteenth century, so there’s a huge body of tested procedures, the primary technique being visual comparison. Our identifications are critically dependent on having known specimen standards, which is our term for verified examples of known species. When we are making our examinations, we are constantly referring to those curated standards, curated to museum-quality degrees of data management. It is also essential that we stay very current with the latest taxonomic decisions related to species, which are surprisingly fluid and changing all the time. In the last ten to twenty years, the increased use of genetic analysis has led to a lot of rethinking of taxonomic relationships. Whether or not 
a crime has occurred can depend on what species 
name is attached to the victim. If the species name has changed, the law may actually list the species under an old name. So we act as arbiters all the time between the taxonomic specialists and the law enforcement people, and we try to give accurate information to both those constituencies. 


How do you go about collecting standard samples? 


BY: Often we get carcasses from zoos or from wildlife refuges of certain animals. We keep them in our freezer and later put them into a colony of beetles that eat away the meat. We finish the process and then install the bones. We might send the hide off to be tanned, and then it all goes into our catalogue as study specimens. 


EE: Oftentimes it can be more difficult than that. For instance, when sturgeon was added to the listings of endangered species, Ken made two trips to Russia, first with the genetics supervisor of our lab and then with the chief of our law enforcement division to obtain sturgeon standards, and came back empty-handed both times. Many times, the challenge to obtain comparison standards is greater than the actual identification work. 


KG: If we’re working on endangered species, by definition there are relatively few of them available as standards. Going out to the field to collect one can be a tough thing. Shark finning is becoming a fairly significant issue to us. If the sharks start appearing in the CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) listings, we know that we’re going to have to come up with fin collections from some 427 species of sharks and rays in order to be able to distinguish between the microtome-thin slices of shark fin that show up in the Asian medicinal markets. 


Are there limits to morphology’s ability to distinguish between species? I imagine identification becomes difficult when you just have a few bone samples and you are trying to differentiate between, say, two closely-related species of deer. 


EE: It depends on the bone type. There are certain bones that are indistinguishable across families and others that are specific to species. 


BY: For example, rib bones are pretty nondescript. But teeth are extremely diagnostic. There’s a whole array of relative value to certain skeletal elements that could allow you to do identification. We do identification of species, but we also do individualization; that is, match pieces of an animal back to a specific animal carcass. Individualization carries a lot of weight in the courtroom because this is where you’re actually connecting the victim to the crime scene or to the alleged criminal. That’s not done with morphology all the time, although it is possible. This is where genetics really shines. 


Is genetics the area where the most progress in forensics is being made? 


KG: You’re delving into a touchy issue among different generations of forensic scientists. I’m from an earlier one
that puts a lot of faith in the examination of trace evidence and morphological structure. Some famous international labs have discarded their trace evidence examination capabilities in favor of just doing DNA analysis. I think that’s a mistake. There’s much more information to be gained from evidence than you get from just a DNA analysis. DNA sequencing is a powerful tool, no question about it, but it doesn’t answer everything. For instance, DNA isn’t useful for a broad unknown. If an investigator sends us a chunk of meat from a suspect’s freezer and asks us to run a DNA analysis to determine the species-source, that can be a difficult job, even if we have all of the relevant databases … which we probably don’t. 


EE: Actually, I’d say that DNA doesn’t have any shortcomings in terms of potential data information to be gained. If anything, the shortcoming with DNA is the status of the evidence when it arrives here. We might have evidence that arrives in a compromised condition because it was found in Florida, where it’s hot and humid and bacteria and enzymes have digested the DNA chains. Ideally, all our evidence would come from Alaska in the winter, where it’s frozen solid and all of the evidence characteristics are preserved. The often compromised condition of our evidence is a big difference between forensics and other types of scientific research. 


What are the different ways in which you might analyze a piece of evidence that comes into the lab? 


PT: Here’s an example that hasn’t exactly happened, but is completely plausible. We could get in a large dead canid, that is a member of the dog family. We might first ask how it died. It goes through pathology for determination of cause of death, and then over the course of the pathology exam, our pathologist finds a bullet. So the bullet goes off to ballistics. We would also need to ask what species it is. There are many hybrids between wolves and dogs, so species identity can often be a vexed question. A sample tissue will go to genetics. In addition, the skull may be prepared in our bug colony to be looked at by Bonnie, who is an expert in canid skull identification. In the course of the cause-of-death determination, our pathologist could find in the stomach a mass of hair, bones, and feathers. He’d send the feathers to me, and I would look at them microscopically to determine what type of bird this canid had eaten. The hair and bones, if they’re mammal bones, would go to Bonnie, and she would identify the mammal component of that meal. Those might suggest that maybe this animal was poisoned as well as shot, that somebody shot it while it was staggering around. So the stomach contents would also go to our chemist, and our chemist would look for pesticide or deliberate poisoning residue. So in one single case every analyst in the lab might be needed to make the complete analysis that the investigator in the field would like to get. And there’s really no lab in the world like this one, in terms of the capability we have to make that integrated analysis. 


KG: And then you also have the conniving nature of our suspects, who might have rigged the scene to make it look like the wolf had taken down a calf, thus allowing them to shoot it, or in fact the wolf had been baited into the scene with a still-born calf, so we have two interesting necropsies to perform and a story to unravel. It’s actually quite a bit of fun to work these cases, but you do have to enjoy figuring out puzzles.