Thanks, David! This is a really helpful explanation.
Gary Brower Unincorporated Arapahoe County > On Sep 13, 2022, at 4:33 PM, David Suddjian <[email protected]> wrote: > > Hi CoBirders. Sorry for another post from me today, but my summary of > Buff-breasted Sandpiper high counts prompted questions about using eBird > graphs. I hope this brief summary is useful. Also attached as a pdf. --David > > > > Many eBirders may not be familiar with or even aware of the graph features > you can access from Bar Charts. This was how I dove a little deeper into the > Buff-breasted Sandpiper (BBSA) story, and a feature I’ve used to help > understand status and distribution in my Bird Bombs. > > In Explore, select Bar Charts and then proceed to choose whatever region you > are interested in. You can choose the whole state, or individual counties. > (Or you may view a bar chart via a hot spot or region you are looking at). > You can include multiple counties in one chart, so if you want to look at the > Metro area, you can choose those several counties. > > https://ebird.org/GuideMe?cmd=changeLocation > <https://ebird.org/GuideMe?cmd=changeLocation> > When you have a bar chart opened, go to a species of interest and click on > the line graph icon to the right of the species name (circled below in Figure > 1) > > > <Screenshot (121).png> > > Figure 1. Bar chart for Colorado with the line graph icon circled. > > > Then you will see a line graph showing the species’ frequency of occurrence > (% of all complete checklists for the eBird week) (Figure 2). Frequency is > the default graph that is presented, and it is one of the most useful. It is > a linear portrayal of the bar chart image. And there are several other > options listed above the chart, presenting different measures (Figure 2). I > used the High Count option to look at BBSA, but in general the Abundance > graph is very useful for looking at seasonal change and comparing among > species. The different measures are defined from a link at the bottom of each > graph page. I recommend reading the explanations. > > > > <Screenshot (122).png> > > > Figure 2. Frequency graph for BBSA in Colorado. Note options above the graph. > > > Above each graph are options to Change Species or Change Date (Figure 2). > Change Species allows you to switch to a different species, but also to view > up to 5 species at once. This is excellent for comparing timing and relative > numbers among similar species. Here is a graph of comparing BBSA with some > other rare shorebirds (Figure 3). Of these rarer but regular shorebirds I > selected, we can see that the AMGP occurs more often than the others, BBSA > and SBDO peak earlier and share similar timing, while DUNL is later than the > others. > > > > <Screenshot (125).png> > > Figure 3. A comparison of frequency of occurrence for four rare but regular > shorebirds. > > > If you Change Date, you have the option to show consecutive years separately > for one species. Select a range of years at the bottom of the Change Date > screen and choose the start year and end year (up to 5 years) and click the > box to show separate years (Figure 4). > > > > <Screenshot (126).png> > > > Figure 4. From Change Date you can select different years or a range of > years. Click on the box if you want to show consecutive years for one species. > > > Now you can compare BBSA over several years (Figure 5). The graph shows that > BBSA frequency is always very low, and that while there is a general peak in > late August to early September, each year is a little different where the > records fall and the season peaks. The best time seems to be a mere 3-week > period at best, most years. Wow there is a lot to learn here. > > > <Screenshot (127).png> > > > Figure 5. BBSA frequency over five years 2015-2019, > > > David Suddjian > > Littleton CO > > [email protected] <mailto:[email protected]> > > > -- > -- > You received this message because you are subscribed to the Google > Groups "Colorado Birds" group. > To post to this group, send email to [email protected] > For more options, visit this group at > http://groups.google.com/group/cobirds?hl=en?hl=en > <http://groups.google.com/group/cobirds?hl=en?hl=en> > * All posts should be signed with the poster's full name and city. Include > bird species and location in the subject line when appropriate > * Join Colorado Field Ornithologists https://cobirds.org/CFO/Membership/ > <https://cobirds.org/CFO/Membership/> > --- > You received this message because you are subscribed to the Google Groups > "Colorado Birds" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/cobirds/CAGj6Rork5nErEbj9LbsPSmVV%3DwjuJ-3KwaXOZ-dhTKLnGUt3rQ%40mail.gmail.com > > <https://groups.google.com/d/msgid/cobirds/CAGj6Rork5nErEbj9LbsPSmVV%3DwjuJ-3KwaXOZ-dhTKLnGUt3rQ%40mail.gmail.com?utm_medium=email&utm_source=footer>. > <A Quick Look at Using eBird Graphs.pdf> -- -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To post to this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/cobirds?hl=en?hl=en * All posts should be signed with the poster's full name and city. Include bird species and location in the subject line when appropriate * Join Colorado Field Ornithologists https://cobirds.org/CFO/Membership/ --- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/F5DB5C9E-2E92-4B42-93B5-F9674EEFA79D%40gmail.com.
