PLOS Science Wednesday: Hi Reddit, it’s PLOS Ecology Community Editor Jeff Atkins joined by the five Ecology Reporting Fellows, and we’re answering questions from #ESA2016 about a ONE article modeling anthropogenic impacts on California wildfires – Ask Us Anything!



Hey Jeff!

Mann et al. present a spatially-informed regression which ironically doesn't incorporate spatial information. Their methods or results or justification do not assume spatial autocorrelation in any capacity. Nor are there any appropriate spatial weighting matrices used to downweight spatial nonrandomness. They instead rely on zero inflated Negbin regression to tell the story. I think this is a slight oversight that needs to be corrected because the probability a given cell may experience a fire event is most likely going to be correlated (i.e., not independent of) the conditions of the neighboring cell. Zip neg bin still assumes random clumping in the responses, but that there are more zeroes than expected between observed events. The random clumping is a feature of sampling distribution, not a feature of space. Therefore, I have some strong worries about their model specification. The results may not change much, but nevertheless, the use of spatial data without use of spatial methods is a bit concerning.

Do you know what was the justification for not actually using spatially-weighted negbin regression?



Jeff here . . . Thanks for the question--it's a good one! Using spatial weighting matrices here could definitely be a valid inclusion, based on what little I do know about them. Spatial autocorrelation and how to account for is something I have been concerned about in my own work as well where I have been looking at subcanopy shrub expansion in temperate forests.

I think it would be a wonderful extension of this work to look at a model comparison (provided the other models include some type of anthro/urban density component) to see how the preform. But in short, no I don't know the justification to not using spatially-weighted negbin regression. I would love to learn more, do you have papers or sources you can link to?

For a more indepth response, I would follow up with Dr. Mann for more specifics.

Great question!

What is PLOS's stance on the US Forest Service's continued use of the "Smokey the Bear" campaign to brainwash the American public into believing that wildfire is bad for our forest ecosystems, when clearly wildfire is a natural and beneficial component to any forest?


Jeff again . . .

We had a recent fire break out in Shenandoah National Park, in Virginia a couple of months ago, and there was a lot of concern and uproar that the park service was not actively trying to suppress the fire. Since it was in the backcountry, the park service drew hold lines near property, but otherwise just let the fire burn.

There was good outreach from the park on local media outlets and on Facebook to educate people about wildfire and how it is beneficial and a natural cycle.

Agreed, outreach to educate the public is huge. I am mixed on the Smokey the bear thing too.

There is also a disconnect in the purpose of the Forest Service in some people's minds. The Park Service preserves land, but the USFS is part of dept. of Ag and they are they to grow forests for whatever use. I think that is another distinction as well.

The predicted increase in fires in heavily populated areas is concerning. Do you know of any successful case studies for decreasing fire prevalence that we can draw on to guide policy changes? Perhaps focusing on changing human behavior?


Jeff here . . .

That is a brilliant question. We are experiencing some slow internet here, sorry about the delay.

I am not aware of any. I wonder if there are any from European nations?

Kelsey here -

A bit unrelated to fire, but sticking with the "novel ecosystems in the anthropocene" theme of ESA - I went to a lot of great talks on anthropogenic effects on bees and other pollinators. If anyone has any interest in that topic/questions to ask, I'll do my best to answer!

I'll also be live tweeting the Pollination session at ESA starting at 1:30. Follow my tweets @PLOSEcology


Jeff here . . .

Kelsey, what has been the coolest bee related thing you have seen?

Can you give some estimates about the costs currently involving the effects of human activity and climate change on fire activity in California? Future costs / trends ?


Kelsey from PLOS Ecology here, starting things off -

The authors found that between 2012 and 2014, $230 million per year was spent on damages to structures from fire. And $5.18 billion was spent on wildfire suppression alone between 1999-2011.

Given the authors' predictions about the increase in fire activity, particularly in developed/populated areas, I think the safe assumption can be that costs will only increase.

Can you give some estimates about the costs currently involving the effects of human activity and climate change on fire activity in California? Future costs / trends ?


Hey this is Jeff. One of the concerns, as far as costs, is the escalating costs incurred by the Forest Service on fighting wild fires. Over 2 billion in 2015 (

Anecdotally, there is concern that a lot of that money could be used to do research or build capacity and is instead going to fight wildfires that if there were not developed areas that were being threatened, might not be spent on wildfire suppression.

Additional Assets


This article and its reviews are distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and redistribution in any medium, provided that the original author and source are credited.