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The United States, like most other nations, has committed to protecting 30% of its land and oceans by 2030—known as 30-by-30—concurrent with societal goals such as reversing ‘inequitable access to the outdoors’. Although protected areas (PAs) in the United States are generally closer to wealthier and less racially diverse neighbourhoods, we find that marine PAs are closer to wealthier but more racially diverse neighbourhoods compared with terrestrial PAs. Achieving 30-by-30 may exacerbate inequitable access to nature because it will require more PAs inland, instead of near diverse coastal cities.

All code and data for the reproduction of all the results and figures in the main manuscript, Related Publication: "Comparing Access to US Marine and Terrestrial Protected Areas" Authors: Anna Lou Abatayo (*,a), Madelon van Adrichem (a), and John Lynham (b,c) *Corresponding Author. Email: anna.abatayo@wur.nl (a) Environmental Economics and Natural Resources Group, Wageningen University and Research (b) Department of Economics, University of Hawaii at Manoa (c) UHERO, University of Hawaii at Manoa Details on the uploaded reproduction files and how to use them can be found in "~ReadMe.txt".

Fish stock assessment often involves manual fish counting by taxonomy specialists, which is both time-consuming and costly. We propose an automated computer vision system that performs both taxonomic classification and fish size estimation from images taken with a low-cost digital camera. The system first performs object detection and segmentation using a Mask R-CNN to identify individual fish from images containing multiple fish, possibly consisting of different species. Then each fish species is classified and the predicted length using separate machine learning models. These models are trained on a dataset of 50,000 hand-annotated images containing 163 different fish species, ranging in length from 10cm to 250cm. Evaluated on held-out test data, our system achieves a $92\%$ intersection over union on the fish segmentation task, a $89\%$ top-1 classification accuracy on single fish species classification, and a $2.3$~cm mean error on the fish length estimation task., Comment: Under review

The data is collected through laboratory experiments on a dynamic common pool resource game, where, in an infinitely repeated number of rounds (i.e., game ended randomly), individuals made decisions about whether to exert a high or a low effort level to extract resources. Experiments were conducted using the student sample (consent provided and ethics approved) at the University of Hawaiʻi at Mānoa. A total of 8 sessions, 2 for each of the 4 treatments, were run with exactly 20 participants within a session. Individuals made decisions in groups of 10. Communication between any participant was not allowed. A session is randomly assigned (1) to vary whether the inflow of resources at the beginning of each round is high or low, and (2) to allow participants to either financially punish or socially punish defectors. A financial punishment resulted to a loss in profit for the punished while a social punishment displayed the words “You have extracted too much! You're being greedy!” on the computer screen of the punished. Individuals were assigned subject ID numbers and interacted using their subject IDs. The data is useful in understanding how resource inflow and type of punishment affects individual resource extraction behavior. The data could also be combined with other publicly available common pool resource datasets for a meta-analysis on individual behavior in the commons.

Climate change is altering the dynamics of common pool resources around the world. We design an experimental game that varies both the flow of natural resources and the group punishment mechanisms available to resource users. Our experiments show that subjects are more likely to over-harvest when resource flows are high. But group punishment mechanisms that rely on social ostracism (as opposed to fines or fees) are more effective at mediating the desire to over-harvest when resources are booming. This suggests that collective management systems based on social norms, exclusion, and ostracism may be more resilient to unexpected changes in resource dynamics and supports bottom-up, as opposed to top-down, management of common pool resources.

The dataset comes from a laboratory economics experiment on resource booms and group punishment in a coupled social-ecological system. It contains 3,060 observations from 8 sessions with exactly 20 individuals per session. The data contains 33 variables, including individual decisions per round during the experiment as well as socio-demographic information.

When are risk preferences stable and when do they change? In general, individual preferences tend to be consistent across time and space but extreme shocks, such as natural disasters, appear to change how people make economic decisions. We conduct an artefactual field experiment with fishers on a remote island in the Philippines and investigate the effect of Typhoon Bopha on risk preferences, along with fairness and time preferences. The typhoon destroyed coral reefs and reduced populations of fish, weakening food security. Comparing individuals from communities that were directly hit by the typhoon with those that were not, we observe evidence that those affected by the typhoon are less risk averse. Stratifying our sample by gender, we observe strong evidence that females affected by the typhoon are more risk-loving than females unaffected by the typhoon. These results are consistent with the hypothesis that extreme negative events cause individuals to be more willing to accept greater risk in return for a larger financial reward.

We studied how communication media affect trust game play. Three popular media were considered: traditional face-to-face, Facebook groups, and anonymous online chat. We considered post-communication changes in players’ expectations and preferences, and further analyzed the contents of group communications to understand the channels though which communication appears to improve trust and trustworthiness. For senders, the social, emotional, and game-relevant contents of communication all matter, significantly influencing both their expectations of fair return and preferences towards receivers. Receivers increased trustworthiness is mostly explained by their adherence to the norm of sending back a fair share of the amount received. These results do not qualitatively differ among the three communication media; while face-to-face had the largest volume of messages, all three media proved equally effective in enhancing trust and trustworthiness.

The ongoing emission of greenhouse gases (GHGs) is triggering changes in many climate hazards that can impact humanity. We found traceable evidence for 467 pathways by which human health, water, food, economy, infrastructure and security have been recently impacted by climate hazards such as warming, heatwaves, precipitation, drought, floods, fires, storms, sea-level rise and changes in natural land cover and ocean chemistry. By 2100, the world’s population will be exposed concurrently to the equivalent of the largest magnitude in one of these hazards if emmisions are aggressively reduced, or three if they are not, with some tropical coastal areas facing up to six simultaneous hazards. These findings highlight the fact that GHG emissions pose a broad threat to humanity by intensifying multiple hazards to which humanity is vulnerable.

Direct face-to-face communication has traditionally been found to be more effective for fostering economic cooperation than any form of indirect, mediated communication. We inquire whether this is still the case since most young adults routinely use texting and online social media to communicate with each other. We find that young adults in our laboratory public goods experiment are just as adept at finding and sustaining cooperative agreements when communicating within a Facebook group and through online chat as they are in person., Direct face-to-face communication has traditionally been found to be more effective for fostering economic cooperation than any form of indirect, mediated communication. We inquire whether this is still the case since most young adults routinely use texting and online social media to communicate with each other. We find that young adults in our laboratory public goods experiment are just as adept at finding and sustaining cooperative agreements when communicating within a Facebook group and through online chat as they are in person.

Direct face-to-face communication has traditionally been found to be more effective for fostering economic cooperation than any form of indirect, mediated communication. We inquire whether this is still the case since most young adults routinely use texting and online social media to communicate with each other. We find that young adults in our laboratory public goods experiment are just as adept at finding and sustaining cooperative agreements when communicating within a Facebook group and through online chat as they are in person.

It is widely believed that there is strong experimental evidence to support the idea that exogenously imposed regulations crowd out the intrinsic motivations of common pool resource (CPR) users to refrain from over-harvesting. We introduce a novel experimental design that attempts to disentangle potential confounds in previous experiments. A key feature of our experimental design is to have the exact same regulations chosen endogenously as those that are imposed exogenously. When we compare the same regulations chosen endogenously to those externally imposed, we observe no differences in extraction levels among CPR users in a laboratory experiment. We also observe no differences between weak external regulations and no regulations, after controlling for a potential confound. However, when we add communication to our endogenous treatment, we observe significant behavioral differences between endogenous regulations with communication and exogenous regulations without communication. Our results suggest that externally imposed regulations do not crowd out intrinsic motivations in the lab and they confirm that communication facilitates cooperation to reduce extraction.

It is widely believed that there is strong experimental evidence to support the idea that exogenously imposed regulations crowd out the intrinsic motivations of common pool resource (CPR) users to refrain from over-harvesting. We introduce a novel experimental design that attempts to disentangle potential confounds in previous experiments. A key feature of our experimental design is to have the exact same regulations chosen endogenously as those that are imposed exogenously. When we compare the same regulations chosen endogenously to those externally imposed, we observe no differences in extraction levels among CPR users in a laboratory experiment. We also observe no differences between weak external regulations and no regulations, after controlling for a potential confound. However, when we add communication to our endogenous treatment, we observe significant behavioral differences between endogenous regulations with communication and exogenous regulations without communication. Our results suggest that externally imposed regulations do not crowd out intrinsic motivations in the lab and they confirm that communication facilitates cooperation to reduce extraction., It is widely believed that there is strong experimental evidence to support the idea that exogenously imposed regulations crowd out the intrinsic motivations of common pool resource (CPR) users to refrain from over-harvesting. We introduce a novel experimental design that attempts to disentangle potential confounds in previous experiments. A key feature of our experimental design is to have the exact same regulations chosen endogenously as those that are imposed exogenously. When we compare the same regulations chosen endogenously to those externally imposed, we observe no differences in extraction levels among CPR users in a laboratory experiment. We also observe no differences between weak external regulations and no regulations, after controlling for a potential confound. However, when we add communication to our endogenous treatment, we observe significant behavioral differences between endogenous regulations with communication and exogenous regulations without communication. Our results suggest that externally imposed regulations do not crowd out intrinsic motivations in the lab and they confirm that communication facilitates cooperation to reduce extraction.

Rising sea levels necessitate careful consideration of different forms of coastal protection but cost-benefit analysis is limited when important non-market social costs have not been measured. Seawalls protect individual properties but can potentially impose negative externalities on neighboring properties via accelerated beach loss. We conduct a hedonic valuation of seawalls in two coastal California counties: San Diego and Santa Cruz. We find no strong evidence to suggest that the presence of a seawall is positively correlated with the value of the home protected. However, we find that seawalls are strongly negatively correlated with the value of neighboring properties in Santa Cruz but not in San Diego county, suggesting that the effect of seawalls depend on certain geographical attributes. Our results are robust to accounting for the public-good nature of locational attributes and the potential spatial dependence of housing prices. Simulation reveals that doubling the extent of seawalls in San Diego and Santa Cruz could reduce property tax revenues by $7 million and $54 million, respectively.