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PNHP / COA

Pennnsylvania Conservation Opportunity Area Tool development scripts
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AOI proportion threshold for determining SGCN Occurrence #95

Open dyeany opened 7 years ago

dyeany commented 7 years ago

@ChristopherTracey , we should decide whether or not to create a minimum acreage/AOI proportion threshold at which we determine a SGCN occurrence at a given probability should be "counted". Or do we just want to include any spatial intersection?

ChristopherTracey commented 7 years ago

One issue is that the smallest species feature we map is about about 0.5 acres. Do we set the threshold below that? What if the species occurs right on the line and half of it is in the selected PU?

dyeany commented 7 years ago

Are there actions that make sense for a quarter acre? Generally? I guess, what minimum scale do we say is big enough for actions to make a difference for a given SGCN?

Related – do users want to know what proportion of their AOI is “occupied” by SGCN?

ChristopherTracey commented 7 years ago

Isn't that the field of conservation planning? :)

ChristopherTracey commented 7 years ago

Picking back up on this, I think there are actions that function at the sub-acre scale (eg. invasive control) and have a positive impact on the SGCN. I think we have to report every action (except those are geographically) not appropriate.

ChristopherTracey commented 7 years ago

Regarding the proportion issue, from the call the other day, it seems like Dan was interested in the same thing. It's not a big thing to report the number of PUs that have an SGCN in the report somewhere. Do we report the number of PUs for each species as each OccProb?

dyeany commented 7 years ago

Reporting proportion ought to be standardized. I'm not sure just # of planning units will be enough. But if we can report % of AOI - even if 2/10 PUs = 20%, I wonder if that would be more desirable.

I do think that most actions, when considering home range or territory size for most vertebrates (which is the focus of the WAP), is likley to be >1ac in size. But @ChristopherTracey , are you suggesting that any SGCN intersection should be reported? So, no minimum acreage threshold, right?

ChristopherTracey commented 7 years ago

Yes, I meant proportion.

I'm curious about a threshold, but I think it needs to be pretty small. I think this is part of the testing you may want to undertake. That is, look at some sites where we know the the intersection of a SGCN poly and the PU is really small and see what the tool spits back with and without the threshold.