Saturday, October 1, 2016

Recording Geospatial Data

Considering my career is in GIS (geographic information systems), I've rarely mentioned anything about mapping in my blog posts and only have one post that discusses the pros and cons of different ways to display butterfly records, found here.
In this post, I will attempt to give a brief overview of some common methods of recording data and provide some tips for the method that has worked best for myself.

GPS Unit
GPS (global positioning system) units come in many shapes and sizes, the most common of which are small hand-held units, such as the Garmin eTrex, and vehicle navigation units, such as the Garmin Nuvi. I personally prefer Garmin products for the best results and user-friendly interfaces, although Magellan is another popular brand. I won't go into all the pros and cons of the two brands, there are plenty of reviews on the internet for that! If you really want to study the nitty-gritty details, this is a good place to start:
A serious lepidopterist needs to record detailed location information for any butterfly records, therefore a GPS device is essential. While I used three different GPS units through my early years of records-keeping, I have now switched over to the following system because 1) it is combined with my phone, so I don't have to carry extra equipment, and 2) I find it easier to use and more flexible.

Avenza PDF Maps
Avenza is a free app for Apple and Android devices. It uses the built-in GPS in your smart phone to tell you if you are on a particular map, and allows you to add waypoints and track a path (hiking, biking, etc.) similar to a standard hand-held GPS unit. This app came out a few years ago and has been rapidly gaining in popularity. Many companies are now using it to collect data because it is so easy to use, reduces the equipment (everyone has a phone, now they don't also need a GPS unit), and allows them to use custom company maps. Avenza has a map store where you can purchase standard maps (on Apple devices, it is linked through your iTunes purchase account). They are constantly adding new maps and have a wide range of options, anywhere from historic maps to standard road maps, National Geographic Trails Illustrated maps (my personal favorites!) and other recreation maps. Some maps are free, but most range from around $2 to $15 and are comparable to or slightly cheaper than paper versions.

Because I am a GIS analyst by profession, I am able to make my own custom maps in ArcMap (ESRI software) and upload them to the Avenza app on my phone. However, I primarily use the National Geographic Trails Illustrated maps purchased through the Avenza store. They have proved to be the most accurate for trails here in Washington and I like the cartographic style (symbols and colors). The specific maps I have purchased are:
821::Columbia River Gorge National Scenic Area
822::Mount St. Helens and Mount Adams
825::Alpine Lakes Wilderness
It appears their 810-series are Oregon maps and 820-series are Washington. Most of these maps are currently $12 and include both sides of the paper version of these maps (i.e. the purchase will download two PDF maps).

Another series I find useful are the Benchmark Recreation Maps. They are a single map of an entire state, exactly the same as you find in the front of Benchmark Atlases. Avenza doesn't offer them for all 50 states yet, but most of the western states, including Oregon and Washington, are available for only $5 each! While they lack the detail you'll see in the trails maps, if you are in an area you're very familiar with or otherwise don't need to see any of the details, they are very useful as a cheap alternative for simply allowing you to save waypoints to the map to store the same information you would on the detailed maps. I used these Benchmark maps for all the states I visited during my two week road trip this summer (the LepSoc conference I blogged about). They worked great because 1) I wasn't always sure which location I'd be catching butterflies in, so a statewide map covered my bases, 2) it was cheaper than buying detailed PDF maps of everything, and 3) I still like to be old-school and use paper maps (mostly state gazetteers/atlases) for general navigation and trip planning. So, I planned out the general route using my road atlases (yes, I brought a book bag full of them!), entered the general route into my Garmin Nuvi GPS for turn-by-turn navigation, then saved placemarks in Avenza whenever I stopped, both to mark the coordinates and easily enter notes about the butterfly species I saw, all of which I transferred to my notebook each evening for easy reference and as a backup.

I strongly encourage everyone to try out this app, it may not be for you, but it is certainly worth trying if you are looking for a simple and easy way to record information when you're out and about in the woods!
Avenza app - views 1 and 2
View 1 is what you see when you open the Store in the Avenza app. You can either browse the maps by group, such as clicking on National Geographic and then the "Trails" option, then scroll through the list of maps, or you can click on the Find Maps button at the top of the screen, which will take you to something similar to view 2. You can pan around the map and zoom in or out to areas of interest to see if there are any maps for that area (the blue pins), or you can click in the gray search box at the top and type in a keyword, or a specific map title such as the ones I listed above.

Avenza app - views 3 and 4
Once you have purchased a map or uploaded your own custom maps, they will appear as shown in view 3. As you can see under each title, it tells you if you are "on map" or the general direction and how many miles away you are from that map. This makes it easy to scroll through the maps and find the one you need to view if you have a bunch of them. View 4 shows part of the Benchmark Washington recreation map with several pins I saved during my trip to Goat Peak, Slate Peak, and the Sinlahekin last month. The blue circle in the middle of the screen is where a pin would be dropped if you added another one. The lat/long coordinates at the bottom of the screen correspond to the point in the center of the blue circle; they change as you move the map around.
If you click on the arrow in the bottom left corner of the screen, it will turn blue and the map will center on your current location if you are within the extent of the map, otherwise it will say "not on map".

Avenza app - views 5 and 6
Views 5 and 6 show one of the National Geographic Trails maps with several pins that I've color-coded for different trips to the same location. When you touch any of the pins, you will see a pop-up, as in view 6, with the pin name. If you touch the "i" button it will open up the attributes of that pin (aka placemark).

Avenza app - views 7 and 8
View 7 is an example of what you'll see when you open the attributes of a pin/placemark. By default, when you drop a pin on the map it will have a name of Placemark 1, Placemark 2, etc., but you can edit it to whatever you want by clicking on the little gray X button on the right and typing in a new name, such as my note here for "Coronis Fritillary Females". Note that it also saves the date and time below the name. This is also where you can change the pin color or style (Icon button), the description (a box where you can type detailed information, such as a list of butterfly species seen at the location), or add photos (it will ask if you want to take a picture or choose one from your camera roll). As long as you keep those photos in your camera roll/on your phone, they will be available through this app. You can export them as part of the KML file and they will be viewable in Google Earth. Once you export them as a KML, you can delete the photos from your phone if you wish (the KML will have an embedded copy of them). If you click on the Location button you can view the full lat/long coordinates for that point. You can also edit the Layer attributes/schema, but I rarely mess with that. See view 9 below for more on that.
View 8 shows some of the options available in the map (click on the wrench button in the bottom right corner of the screen in the map view to get here). The measure tool allows you to measure distances or areas on the map by hand. If you wish to track your movements during a hike or bike ride, use the Record GPS Tracks tool. It will record information even if you close the app. This tool needs to have a clear GPS signal, so I recommend keeping your phone in a shirt pocket or outside pocket of your backpack. I covered it up too much one time and it kept losing the signal, so the final track had lots of sharp zigzags and said I traveled twice as far as I actually did!

Avenza app - views 9 and 10
View 9 shows several layers that are within a single map. In views 5 and 6, if you click on the symbol on the bottom right that looks like a pin with three lines next to it, it will take you to this view. As you can see here, I've grouped the placemarks (pins) by year to help separate different trips to the same area. It also shows one layer, the "Lost Creek Old Growth", which is a polygon feature I exported from ArcMap and brought into Avenza for a hiking trip. The two buttons on the bottom right are the import (left) and export (right) options. When you click on the export button, you'll see something like view 10. You can choose to email a KML file (as shown) or pick a different option and format. If you choose the email option, once you click Export (top right of screen), it will open an email window where you can enter a recipient (I usually send to myself) and it will automatically attach the KML file. You can then open the file in Google Earth on any computer to view your points! It usually keeps the same point color and style as seen on the maps, and you can click on them in Google Earth to view the data (same info as in view 7), including any photos that you may have added.
The KML files are also easy to bring into ArcMap using a conversion tool.

Overall, Avenza is very easy to use but takes a little bit of exploring to figure out where all the options are. They do have a "Getting Started" map that tells you what most of the buttons do, but I learned more just by playing around with everything. It's almost impossible to mess up anything, so just explore and experiment. Go to their website for more information:

In summary, these are my recommendations...
Save good butterfly locations using a vehicle navigation GPS (eg. Garmin Nuvi) and Avenza.
When I'm driving around in the mountains and find a particularly good butterfly spot in an area I'm unfamiliar with, I'll save the location in my Garmin Nuvi so that I can navigate directly to it in the future. If I collect any butterflies in that spot, I'll also save a waypoint in Avenza so I have the date, time and lat/long coordinates for future reference.
Navigate to butterfly locations using a vehicle navigation GPS.
You'll need a GPS unit that provides turn-by-turn navigation. A smart phone may substitute for this, but it is usually hard to find a particular location in the mountains on your phone.
Record butterfly data in Avenza PDF maps.
Allows you to save waypoints that include lat/long coordinates, date and time, along with any photos you might take with your smart phone, and is very easy to enter additional notes. Also will record hiking tracks with approximate length and elevation changes. Is easy to export all points and tracks as a KML file that can be opened in Google Earth or converted to a shapefile for use in ArcMap (GIS software).

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