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BioBlitzes and gatherings to explore a natural area are wonderful ways to engage people in biodiversity but often the data gathered and its importance is overlooked. In the past this might have been because the data was only locally available or not available at all but with platforms like iNaturalist it has become much easier to share such information and make it available to the public.

However, even with the data being made public the impact of such gatherings and efforts can go unnoticed. While most would agree that the data generated is very important it is also important to emphasize the efforts to gather this data by looking at impact on the data as a whole a small number of people can have.

Below is an analysis of a recent gathering at Elephant Mountain Wildlife Management Area (WMA) near Alpine, Texas. The emphasis here is more about the impact of the gathering on the data collected for the area rather than the specifics of the data on the organisms collected.

The need to do this analysis is to emphasize the importance of BioBlitzes to the understanding of biodiversity of a given area and to think about future efforts and where they can be put to good use.

Sam Kieschnick (sambiology), of Texas Parks and Wildlife, organized an informal iNaturalist gathering at Elephant Mountain WMA south of Alpine, Texas. The event was schedule for April 16 - 19, 2021.

There were around 20 participants and we met at the registration building on Friday evening (April 16). During the weekend some camped at the campground on site while others drove in from Alpine or a nearby location each morning.

The event itself was very informal and we spent the days hiking and driving to various locations taking pictures of anything and everything we ran across. We would gather in the mornings and evenings as a social group but to also share some of our findings for the day.

To examine the impact of the gathering on the data collected in the WMA it is worth looking at observations and numbers of species in iNaturalist for the April event and observations made before the event.

Below is a break down of observations and species visually.

Below is a visual representation of the impact of the iNaturalist event on the number of species observed and identified at Elephant Mountain WMA. An analysis of species is broken down by Kingdom and then by Class for Plants and Animals.

Note: some taxa are not represented because of their absence in the observations.

Species diversity estimates cannot be calculated from the current observations but a species accumulation and rarefaction curve have been constructed for both plants and animals. It is clear that for both plants and animals that the iNaturalist gathering had a significant impact on the number of species of plants and animals added to the observed list. The species accumulation and rarefaction curves were constructed by dividing all of the data into their respective months for the years of 2013-2021. Excel was used to construct the species accumulation curve and EstimateS was used to construct the rarefaction curve.

The main takeaway from the rarefaction curves is that they are not asymptotic indicating that the species estimates should be much higher than what has currently been observed. There is additional evidence for this when comparing Elephant Mountain WMA species observed in iNaturalist compared to that of Big Bend National Park which is only a few miles to the south.

For plants Elephant Mountain WMA has a total of 212 plant species at research grade while at Big Bend there are 610. Big Bend represents a more heterogeneous habitat and a larger surveyed area which are important considerations in species estimates but these numbers (212 and 610) can be used to estimate the minimum and possible maximum of species that could be potentially found at Elephant Mountain.

iNaturalist represents a readily available platform for making observations and for retrieving data. The iNaturalist gathering on April 16-19, 2021 was not only a lot of fun but it also significantly added to the observed species for the area.

Species observations are important for making scientific and management decisions and any review of the diversity of a given area should look at all available data but iNaturalist represents a fast growing data set because it caters to the expert and non-expert alike.

Using tools in iNaturalist it may also be useful to look at observations of other areas to determine the need of other such gatherings in the future.

If you have any questions or comments please direct them to Curtis Eckerman (curtis.eckerman@austincc.edu).