Fieldwork in Parasitology: a Mountain Worth Climbing
The Field Notes section includes tales of trials and triumphs in the field and in the lab. In this Field Note, Dr. Janet Koprivnikar shares tips for how to increase the likelihood that your field work culminates in tales of triumph.
By Dr. Janet Koprivnikar (Associate Professor, Ryerson University)
Undertaking fieldwork is a long and proud tradition in parasitology, and forms a critical part of the research conducted by many investigators. In fact, approximately 45% of all the research papers published in the Journal of Parasitology 2017-2018 involved fieldwork to some extent! But why is fieldwork not even more common than this? Fieldwork is obviously not appropriate, or even possible, for all questions or host-parasite systems; however, you might find yourself hesitating to conduct fieldwork based on three major issues: i) logistics; ii) perceived benefit; and, iii) fear of the unknown. In many ways, it’s a bit like contemplating a hike up a mountain.
Looking Up at the Mountain from Below
It can admittedly be a bit discouraging to consider the logistics associated with fieldwork. Applying for sampling permits alone can be timely and frustrating. There is often other required paperwork, including risk management forms, standard operating procedures (SOPs), and post-sampling reporting. If you’re planning on working internationally, or in remote areas, this can mean a considerable time lag between the planning and actual fieldwork phases, making last-minute changes difficult. Fieldwork may be expensive when you factor in the costs of travel, housing, supplies, shipping, vehicle rental, etc.
The perceived benefits of fieldwork can additionally play a role in deciding whether it is worthwhile. It can take a lot of time to obtain sample sizes large enough to be useful (sometimes multi-year studies are needed), student projects can be time-limited, and there can be a trade-off in resources with lab studies that might give more results in less time.
Fear of the unknown can also be intimidating. For instance, if you have no information to work from, it can be daunting to figure out where to sample based on the likely occurrence of your focal organisms, ease of access to sites, and permission to do so. The chances of successful fieldwork can also be unpredictable based on weather, accessibility difficulties, lack of samples, equipment failure, and dozens of other factors.
But Don’t Despair! The View from the Top is Worth It!
So far this does not seem like a great pitch for fieldwork! However, there are many tangible and intangible benefits. And with careful planning, and a willingness to be flexible, the chances of success are greatly improved. Much like escape from common parasites through frequency-dependent selection, fieldwork can also confer a rare allele advantage to researchers doing so because there is strong demand for natural examples, and these are often highly cited. You are additionally collecting valuable future information when undertaking fieldwork, so it is important to think broadly about possible long-term impacts beyond your own immediate research. For instance, fieldwork provides key data regarding baseline occurrences in space and time, and your findings may be included in future meta-analyses to detect general patterns across primary studies. Field sites can also become sources of material for experiments using parasites and hosts that are difficult to maintain in labs. Last, but certainly not least, fieldwork can be inherently enjoyable and impart a sense of accomplishment, which also confers many benefits. Acquiring hands-on, transferrable skills through such unique experiences helps to recruit good students, as well as the chance to make valuable contacts with government agencies, NGOs, and private land owners.
Plan for Success Before Your First Step on the Mountain
There is a lot of great advice out there on how to succeed while in the field, but all will agree that the most important steps occur while you are still inside, just as when you’re packing for your hiking trip. You don’t want to realize that you forgot your rain jacket only as the first drops hit your head. You cannot plan for everything, but there are certain key considerations that usually apply for fieldwork. For instance, as is the case for all empirical research, your sample size needs to be representative and rigorous so that you can make strong conclusions. How many sites do you need to sample? How many individuals at each site? Can you actually achieve the needed level of sampling? Nature will not always cooperate in this respect.
As an example, clustered sampling sites are a common issue for field collections. In this case, will you be able to deal with samples that show a correlation with one another in space or time? Bad data can be defined in many ways, but also includes that which you do not know how to deal with after expending a lot of effort and resources! It’s a bit like driving for hours to reach a trailhead and then realizing that no one brought a map. At the pre-planning stage, consider how you will deal with your data and the tool(s) that you will need. For instance, will these analyses be complex or specialized such that you will need to do some coding or learn particular software packages? An ounce of prevention is definitely worth a pound of cure in this case if you can identify potential problems early on.
Unfortunately, there is no magic formula when it comes to estimating appropriate sample sizes. Consider precedent (similar questions and study organisms) and your planned sampling approach to see how these match your logistic constraints (time, distance, transport costs, permits, etc.). Even your desired data has implications. For parasite-related measures, are you interested in the prevalence of infection, parasite richness, or in multiple aspects? What does that mean for your target sample size? For instance, macroparasite infections are typically highly aggregated among individuals in a given population, and sampling only a few may not capture natural patterns. Will you gather other abiotic or biotic data while in the field? Consider which measures may be of possible interest to you later on, as well as to other researchers. There is bad data, but the worst data is that which you failed to collect and then desperately need later on!
It is also important to recognize that field work can be demanding. Challenging conditions can include extreme temperatures and precipitation, wildlife (including biting insects, and, yes, contracting your own infectious diseases), isolation, water hazards, and even hostile people. While I’ve been lucky enough to mostly avoid close encounters of the large carnivorous kind, walking into a moose at night was memorable enough. Overall, try your best to expect the unexpected. Outdoor conditions can change quickly, including extreme weather. You might also find unanticipated site conditions, so plan for sampling alternatives, extra equipment, extra gear and clothing, food and water, first-aid supplies, spare consumables, and extra time.
However, despite all of your careful pre-planning, things will not always go your way, so have a back-up plan, and a back-up to your back up plan. You can get halfway up the mountain and encounter two feet of snow, so what to do? One common obstacle for fieldwork is a failure to find what you were looking for. For instance, I learned the hard way that minnow traps are really just crayfish buffets. Here, some flexibility can help you to move forward. You might want to ask yourself some of the following questions and revise your plans if appropriate:
· Why is the host and/or parasite absent?
· Can I use what I have found? Have an open mind – you would be amazed at how new questions can find you in the field, and how these may end up fundamentally changing your research plans.
· Can I add some aspects to ask other questions, or to shift emphasis?
· Can I turn this into lab work, or add lab components to bolster my study?
· Would anyone else be interested in what I have found in a different context?
· Are my findings perhaps suited to an exploratory analysis or descriptive/qualitative study if I cannot achieve my original goals?
· How can I use my results as a guide for future sampling efforts?
· Are there potential “value-added” options to consider that were not part of my original study?
· Can I consider existing data and incorporate mine to undertake broader analyses?
In the end, remember that a field study is an experiment, and just like a lab study, these can go wrong if not carefully considered and planned. Plan for what you will do before, during, and after fieldwork. Hiking up a mountain will usually not be easy, but there are reasons why so many people shoulder a pack and head up year after year.