Alaska iNat passes 100k observations & 5k unique taxa: Part II -- Boroughs

Photo by jimmywayne CC BY-NC-ND

This is the second part of a journal post marking AK iNaturalist reaching two recent milestones: 100k observations and 5k unique taxa. If you haven't yet, I would encourage you to read Part I first for background, trends since 2009, seasonality of iNat activity, observations by species groups, and the last remaining Alaskan amphibian to not be IDed on iNat.

An iNaturalist observation has been made in all 29 boroughs and census areas (the Alaskan equivalent to counties, hereafter simplifying to ‘boroughs’). As of 17-Nov-2019 (when I copied the data), the boroughs with the most amount of iNat activity are Sitka, Kenai, and Anchorage. The boroughs with the least amount of iNat activity are Bethel, Kusilvak, and Bristol Bay.
Alaska boroughs and census areas 2008-13

More observers & more observations per borough → more taxa recorded on iNat. In general, there’s a positive relationship between the number of taxa recorded in boroughs on iNaturalist and the number of observers (R2=0.47) and observations (R2=0.87). For every additional observer in an area, roughly about 13 additional observations and 1.5 additional taxa are expected to be recorded on iNaturalist. The boroughs with the most observers? Anchorage (1,023 iNat observers; Alaska's largest population center with almost three times the residents than the next biggest borough), followed by Kenai (910 observers). The boroughs with the most observations? Sitka (38,505 observations), followed by Kenai (12,526 observations). The boroughs with the most taxa recorded? Same pattern as observations: Sitka (2,740 unique taxa), followed by Kenai (1,680 unique taxa).

More people living or visiting a borough for nature → more iNat observers. What explains variation in iNat activity across Alaska boroughs? I spent a bit of time compiling datasets on factors that I suspected might be important: population size, area, visitor volume, visitor volume engaged in nature activities (including wildlife viewing, birdwatching, hiking), broadband service1. Of those, the two factors that seem the most predictive2 in terms of explaining # of iNat observers are (a) borough population, and (b) number of visitors that engaged in a wildlife viewing activity in the borough3. Multiple regression analysis indicated that those two predictors explained a decent 84% of the variance in the number of observers between boroughs. So, there are more iNaturalist observers in boroughs with more residents and more visitors that want to see wildlife -- makes sense, right? This appears true even when controlling for other factors.

More people living or visiting a borough ≠ more iNat observations…. except…. . In contrast to iNat observers, the same pattern does not hold true for iNat observations when looking across all boroughs. In fact, none of the factors I looked at significantly explained differences in observations between boroughs EXCEPT when I dropped a single borough from the analysis. When I looked at all boroughs except for Sitka, the importance of population size and wildlife-viewing visitors re-emerged as significant variables, with a simple model explaining 75% of observation variance4. So, what makes Sitka special?

The Borough of Sitka contains about 1% of Alaska’s population, 0.5% of the state’s area, and >37% of its iNaturalist observations. Sitka has a bit more iNat observers than one might expect based on population or wildlife-viewing visitors, but it has a lot more iNat observations -- so many that it confounds state-wide patterns and analysis mentioned above. You don’t need to run a regression analysis to notice that Sitka iNat is exceptional within Alaska, maybe even the only robust iNat community in the state (if you think differently, however, please feel free to correct me). In the comments of Part I, uber-iNat’r @damontighe said, “@gwark and the rest of the super community there is really showing what can be done by organizing people to contribute and being on top of helping identify things as they roll in. I have yet to take iNaturalist observations in a location that got as much identification help as I had in Sitka.” Over email, I asked @gwark what makes Sitka special, and with his permission, am posting his response here (lightly edited for clarity, like some off-brand @tiwane):

Part of it is my compulsiveness - in addition to the 8000+ observations I've made since I really adopted iNaturalist as my primary way to record natural history observations in at some point in 2016, I've been working through all my photos going back 20 years, 99% of which are from Sitka.

Although a few of us had dabbled with iNaturalist previously, the first person in Sitka who really started using it extensively was Paul Norwood at the beginning of 2015. When I saw how it was working for him, I was convinced that iNaturalist was the way to go.

rolandwirth and kljinsitka both got into iNaturalist during the All Species Community Big Year project that we did in 2017 ( They both really took to it, and have been quite active since that time.

Several other people with >50 observations who are based in Sitka participated in the big year project. A handful have continued to occasionally post observations since then.

I know that I regularly encourage folks to post things to iNaturalist, and I am pretty sure paul_norwood, kilasiak, rolandwirth, and kljinsitka do as well.

I'm not sure if it makes much difference in terms of on-going participation, but I'm pretty compulsive about going through all the observations that come in and trying to identify things. I actually look at all observations from south coastal Alaska (and Haida Gwaii, as well) - but I'm most knowledgeable about things that occur in Sitka, and so am more likely to be able to ID things the closer they are to Sitka.

I think gwark and damontighe hit on a key point re identification help. I wouldn’t really know how to look for the publicly accessible data to confirm it, but my guess is that strong, durable iNat communities are created by enough exceptional individuals that are both creating observations, but also doing a lot of identifications and engagement on other people's observations (as well as connecting with people IRL). People that aren't engaged online, or aren't organized around this platform in person, probably have a much higher likelihood of drifting away. Kudos to Sitka for building community.

I also like the link to the big year project as a starting point for some people to become active users. I think the data are pretty clear that the City Nature Challenge (CNC) brings in a huge influx of iNaturalist users, a fraction of which become longterm active members of the community. I had very briefly talked to the CNC organizers last year about establishing a challenge in Alaska, but the CNC dates -- end of April -- just wouldn't work well for most of the state I think. For those of you Alaskans who didn't join through the Sitka Community Big Year, I'd be curious if you're willing to share: how did you become an active user on iNaturalist?

Tagging folks who commented on Part I: @rolandwirth @loarie @whaichi @carrieseltzer @gyrrlfalcon @awenninger @choess @treegrow @mckittre @connietaylor @paul_norwood

I had planned a Part III to forecast Alaska iNat observations into the future (as is my wont), but I think the spread of the novel coronavirus makes the exercise feel a little less fun and a bit ‘heavier’ now. There’ll be a lot fewer visitors and residents moving around in 2020. Fewer people won’t bother some Alaskans (less crowding on our highways/trails/rivers should be a nice break for us and nature), but it’s going to be a hardship for a lot of neighbors and communities, and an atypical, possibly quite grim year overall.

1 Sources (some more out-of-date than others): Borough Population (copied from Wikipedia 12/1/19: American FactFinder Population. US Census. Retrieved 2019-10-15); Visitor Volume + Wildlife Viewing in Community % + Birdwatching in Community % + Hiking/Nature Walking in Community % (2016 Visitor Volume and Profile; Broadband availability (> 768 Kbps download/ 200 Kbps Upload speeds) (% of households served) (2014)

2 Multiple regression analysis was used to test if borough traits significantly predicted borough observers. The results of the regression indicated that two predictors explained 84% of the variance (R2 =.84, F(2,25)=66.50, p < .000001). Borough population significantly predicted the number of iNaturalist observers (β= 0.003, p < .0000001), as did borough visitors who engaged in a wildlife viewing activity (β= 0.002, p < .000001).

3 The number of visitors that engaged in a hiking or nature walk activity in a borough was also positively related to iNat activity, but was no more significant nor explained more variation than the related variable related to visitors engaged in a wildlife viewing activity. My guess is that the two variables related to visitor nature activities are broadly similar enough that they indicate similar things about the borough, and I chose to focus on the one that appeared to explain more variation. Broadband access and total number of visitors were not significant variables, including when controlling for other factors.

4 Multiple regression analysis was used to test if borough traits significantly predicted borough observations. Dropping Sitka from the analysis was the only way to find a significant model. The results of the Sitka-less regression indicated that two predictors explained 75% of the variance (R2 =.75, F(2,24)=36.27, p < .00000001). Borough population significantly predicted the number of iNaturalist observers (β= 0.03, p < .00001), as did borough visitors who engaged in a wildlife viewing activity (β= 0.02, p < .0001). Models that included total visitor volume, visitor volume engaged in hiking/nature walking, and broadband access did not substantially increase R2.

由使用者 muir muir2020年04月19日 06:26 所貼文


Fascinating post Matt!

發佈由 judygva 約 4 年 前

Your analysis of when and where naturalists are making observations is most interesting. Sitka certainly is a naturalist hub; the way the community has developed is a good model for other communities both physical and virtaul.

I live down in the Salish Sea (near Seattle). I've gotten to know a few fellow iNatters... @wendy5 @ajwright @ewrunn1ng @stewartwechsler and others who are active in my area. I like seeing our virtual communities at work together and would like to help others use iNaturalist.

發佈由 brewbooks 約 4 年 前

Thank you Judy @judygva and @brewbooks. I sort of feel like these two journal posts are amateur anthropology of iNat communities and observer behavior. As Judy is well aware, we had some great meet-ups in the DC area that helped build our little community, e.g.,

發佈由 muir 約 4 年 前

Great analysis @muir !
Yes the Sitka naturalists are sure busy!

發佈由 jasonrgrant 超過 3 年 前


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