Message in a bottle: Open source technology to track the movement of plastic pollution  

By Meagan Ando, SRC intern

The oceans on our planet are intricate, expansive, and provide a home for many organisms while maintaining a delicate balance that makes this environment so inhabitable. However, in recent times, many anthropogenic effects have been threatening them, one of which is the infamous plastic water bottle. Single-use plastic water bottles are all too familiar and are now so common that a majority of people would say they’ve seen one at some point while in natural areas. Based on beach clean-ups performed over 25 years, the International Coastal Cleanup listed these single-use nightmares fifth on the list of reported items of marine pollution (International Coastal Cleanup 2020). But how these pieces of trash end up in the oceans is a major topic of study for scientists worldwide. Because a large amount of debris is thought to originate from inland communities, rivers act as a critical transportation method as large quantities of garbage are dumped into the ocean and have been found to contribute to about 70-80% of all plastics present within the environment (Horton et al. 2017, Sarkar et al. 2019, Law and Thompson 2014). Previous studies have analyzed and modeled the drifting of this waste, which provided a basis for the research that Duncan et al. (2020) wanted to undertake. This group applied GPS networks and satellite technology to modified 500 mL plastic bottles deployed in the Ganges River and the Bay of Bengal. This technology was used due to its possibility to better understand movement through rivers and into marine habitats and how these quantities could potentially pollute open-ocean systems (Jambeck et al. 2015, Schmidt et al. 2017).  

To carry out this study, replicated “bottle tags” were designed and built to replicate movement patterns of a plastic bottle based on size, shape, and buoyancy (Figure 1) (Duncan et al. 2020). Custom electronics were constructed using a computer-aided design model along with O-rings and epoxy to keep the device afloat. The tools were deployed during the National Geographic Sea to Source Ganges Expedition in 2 phases. Ten Phase A bottles were released in the pre-monsoon season and configured to activate every 3 hours to acquire a GPS fix, while a total of 15 Phase B bottles (12 in the river pre-monsoon and 3 in the bay) were deployed and programmed to mobilize every 4 hours to spend up to 30 seconds acquiring a GPS position before returning to a resting state until a satellite passed over (Duncan et al. 2020). 

Figure 1: Visualization of the size, shape, and internal makeup of the deployment devices (Duncan et al. 2020).

Overall, the maximum distance tracked came out to be 2845 km over 94 days. Phase A tags were tracked for an average of 20.1 ± 5.7 days and, when plotted, showed a ‘stepwise’ movement (Figure 2 (a, b, c)). These deployments showed an issue with human interference and consequently being removed from the river due to high urbanization. The 12 Phase B bottles in the river were trailed for an average of 23.1 ± 9.3 days and also showed this ‘stepwise’ displacement (Figure 2 (d)). However, the 3 Phase B bottles deployed in the open-ocean were tracked for an average of 41.6 ± 26.7 days and ended up displaying a more continuous shift over the period of time (Figure 2 (e, f)). The biggest issue with these devices was due to high fishing pressure, in that they would constantly become entangled in fishing gear. To conclude, this proof of concept was successfully displayed in order to help understand how plastic waste such as water bottles is transported through the environment. The capacity for which this satellite technology can be used shows a significant ability to increase and gain new knowledge identifying various habitats associated with the accumulation of plastic debris, which could help conserve those under the most immediate threat of degradation.  

Figure 2: Bottle displacement versus time tracked (Duncan et al. 2020).


Works cited 

Duncan EM, Davies A, Brooks A, Chowdhury GW, Godley BJ, Jambeck J, et al. (2020) Message in a bottle: Open source technology to track the movement of plastic pollution. PLoS ONE 15(12): e0242459. 

Horton AA, Walton A, Spurgeon DJ, Lahive E, Svendsen C. Microplastics in freshwater and terrestrial environments: Evaluating the current understanding to identify the knowledge gaps and future research priorities. Sci Total Environ. 2017 May 15; 586:127–41 

International Coastal Cleanup. Tracking Trash: 25 Years of Action for the Ocean (2020) 

Jambeck JR, Geyer R, Wilcox C, Siegler TR, Perryman M, Andrady A, et al. Plastic waste inputs from land into the ocean. Science (80-). 2015 Feb 13; 347(6223):768–71. 

Law KL, Thompson RC. Microplastics in the seas. Science (80-) [Internet]. 2014 Jul 11; 345(6193):144–5. 

Sarkar DJ, Das Sarkar S, Das BK, Manna RK, Behera BK, Samanta S. Spatial distribution of meso and microplastics in the sediments of river Ganga at eastern India. Sci Total Environ. 2019 Dec 1; 694:133712. 

Schmidt C, Krauth T, Wagner S. Export of Plastic Debris by Rivers into the Sea. Environ Sci Technol. 2017 Nov 7 ; 51(21):12246–53. 

It’s complicated: Understanding non-compliance in small-scale fisheries

By Peter Aronson, SRC Intern

Following regulations can be vital for conservation, yet the world’s realities place pressure onto people, which can incentivize non-compliance. This undermines conservation work and the positive ecological outcomes achieved by it. In the ocean specifically, short bursts of illegal fishing can negate the effects of decades of protection, especially for species whose populations take a long time to recover, like many sharks (Russ and Alcala, 2010). As shark populations have declined globally, conservationists have advocated for shark sanctuaries to be established to protect sharks from exploitation (Dulvy et al., 2014; Ward-Page and Worm, 2017). By understanding the motivations and traits of those not following regulations, strategies can be developed to increase compliance (Keane et al., 2008). Nearly all fishers in the world live in lower-income countries and are engaged in small-scale fisheries, but research on the behavioral drivers of illegal fishing has traditionally focused on recreational fishers in wealthier countries (Bova et al., 2017; World Bank et al., 2012). A group of scientists set out to Myanmar to study fishers’ awareness of, compliance with, and perceptions towards shark fishing regulations.

Figure 1) Populations of some shark species, such as whale sharks, have been in decline globally due to overexploitation. (Victor Researcher (2008). 21 Ton Whale Shark. WikiCommons.)

Myanmar prohibits the capture and sale of whale sharks and has two shark reserves in which shark fishing is not permitted; however, many fishers are unaware of these regulations. The Department of Fisheries also lacks the ability to enforce them. There is additionally ambiguity as the law was declared informally, and it doesn’t address instances of bycatch. Scientists studied five coastal communities they had well-established relationships with where prohibited shark fishing was known to occur. They conducted surveys with fishers, in which fishers could voluntarily answer whether, where, and when they had caught sharks and witnessed others catching sharks. Scientists found 40% of respondents had accidentally or intentionally caught an estimated 4821 sharks in the year prior to the survey (MacKeracher et al., 2020). Of the 58 respondents, 35 reported having caught sharks themselves (MacKeracher et al., 2020). Overall, 49% of respondents were aware of shark fishing rules, with levels of awareness varying among communities (MacKeracher et al., 2020). Shark fishers tended to be younger and not to own their own boat. Most sharks being caught fell within three families: bamboo and epaulette sharks (Hemiscylliidae), requiem sharks (Carcharhinidiae), and hammerhead sharks (Sphyrnidae) (MacKeracher et al., 2020). Nearly 80% of fishers came from the large coastal city of Myeik and sold their catch there and other large coastal cities, while the remainder of fishers from the local communities sold their catch locally (MacKeracher at al., 2020). Fishers who reported catching sharks themselves most commonly said they did so for money, and also mentioned food (MacKeracher et al., 2020).

Figure 2) Boats in the Myeik Archipelago, Myanmar. (Go Myanmar. (2013). The Myeik Archipelago, Myanmar (Burma)[Photograph]. WikiCommons.)

Understanding the levels and potential drivers of illegal shark fishing puts the issue into context and allows resource managers to strategically and effectively plan how to improve compliance. In areas where poverty rates are high and options for alternative sources of income are low, there is a high incentive to fish illegally. Further, communities with limited interactions with fisheries officials are less likely to be aware of regulations, which can contribute to non-compliance. In resource-dependent communities with few options as sources of income, shark conservation efforts can benefit from strategies to reduce fishing pressure by providing incentives for alternate sustainable livelihoods. Further, as most shark fishers are young men, these can be incentives targeted for that demographic. While educational campaigns can improve awareness and compliance, long-term compliance must be achieved by addressing broader issues such as poverty and food security.


Works Cited

Bova, C.S., S.J. Halse, S. Aswani, and W.M. Potts. 2017. Assessing a social norms approach for improving recreational fisheries compliance. Fisheries Management and Ecology 24: 117–125.

Dulvy, N.K., S.L. Fowler, J.A. Musick, R.D. Cavanagh, P.M. Kyne, L.R. Harrison, J.K. Carlson, L.N. Davidson, et al. 2014. Extinction risk and conservation of the world’s sharks and rays. eLife 3: e00590.

Keane, A., J.P. Jones, G. Edwards-Jones, and E.J. Milner-Gulland.2008. The sleeping policeman: Understanding issues of enforcement and compliance in conservation. Animal Conservation 11:75–82.

MacKeracher, T., Bergseth, B., Maung, K. M. C., Khine, Z. L., Phyu, E. T., Simpfendorfer, C. A., & Diedrich, A. (2020). Understanding non-compliance in small-scale fisheries: Shark fishing in Myanmar’s Myeik Archipelago. Ambio, 1-14.

Russ, G.R., and A.C. Alcala. 2010. Decadal-scale rebuilding of predator biomass in Philippine marine reserves. Oecologia 163: 1103–1106.

Ward-Paige, C.A., and B. Worm. 2017. Global evaluation of shark sanctuaries. Global Environmental Change 47: 174–189.

World Bank, Food Agriculture Organization, and WorldFish. 2012. Hidden harvests: The global contribution of capture fisheries, economic and sector work. Report No. 66469-GLB. Washington, DC: The World Bank.

Using Local Fisher’s Knowledge in Marine Conservation

By Megan Buras, SRC Intern

To set historical baselines for conservation actions, scientists are using new tactics to involve fishers in marine management. Gaps in long-term scientific data about species abundance and diversity can lead to mismanagement of exploited ecosystems. Scientists from the University of Aberdeen interviewed 53 fishers in three different ports of northern Italy to use Fisher’s Ecological Knowledge to determine historical baselines for conservation in the Northern Adriatic Sea. These interviews collected data from three different groups, novices (fishermen with 1-20 years experience), experienced (21-40 years experience), and veteran (greater than 40 years experience) fishermen (Veneroni and Fernandes 2021). From the interviews, the scientists were able to determine trends in fish abundance and collect information about generational accounts of degradation in both species diversity and the seafloor. 

Figure 1: The study interviewed fishers across a broad span of experience to determine generational comparisons of species abundance and diversity. (Image via Egor Myznik on Unsplash)

In terms of species abundance, the study found a linear decrease in cuttlefish catch rates, a significant decline in sole populations, and no significant change in the catch rates of red mullet over 60 years (Veneroni and Fernandes 2021). The study found significant differences between old and young fishers in the generational accounts of species’ diversity. This is evidence of something called Shifting Baseline Syndrome. In this paper, Shifting Baseline Syndrome refers to an incorrect perception of the health of the ecosystem due to false information about its past conditions. This syndrome can lead to mismanagement of an ecosystem appearing to be healthier than it truly is. In the generational accounts of species’ diversity, the study found that veteran fishers listed a greater number of depleted commercial species than novice fishers. In the generational accounts of seafloor degradation, the study found that many of the veteran fishers believed that trawling equipment was the primary cause for degradation, while the novice fishers cited high fishing effort. 

Figure 2: The study interviewed fishers in 3 different ports in Northern Italy, including Cesenatico, Rimini, and Cattolica. (Source: Veneroni and Fernandes 2021)

Fisher Ecological Knowledge provided knowledge on the historical trends of species abundance and diversity in the Northern Adriatic Sea. This information was found “often exceeding national and international scientific data sets” (Veneroni and Fernandes 2021). While it is evident through generational comparisons that Shifting Baseline Syndrome is at play here, there are other examples of conservation being impeded due to similar circumstances. Dogger Bay in the North Sea is another example of how long-term human exploitation can cause marine management failure set on incorrect baselines (Plumeridge and Roberts 2017). Gaps in knowledge contributing to Shifting Baseline Syndrome are not limited to the field of marine conservation. Even ethnobotanical research has found a loss of generational knowledge to inhibit people’s perceptions of the environment (Hanazaki et al. 2013). All this information indicates that Fisher Ecological Knowledge should be implemented into local conservation efforts. This study utilized “cultural brokers” or individuals from the community to gain social entry and acceptance. This highlights the importance of cultivating relationships with local fishers and community members to better protect and understand local environments.


Works cited

Hanazaki, N., D. F. Herbst, M. S. Marques, and I. Vandebroek. 2013. Evidence of the shifting baseline syndrome in ethnobotanical research. Journal of Ethnobiology and Ethnomedicine 9:1-11.

Plumeridge, A. A., and C. M. Roberts. 2017. Conservation targets in marine protected area management suffer from shifting baseline syndrome: A case study on the Dogger Bank. Marine pollution bulletin 116:395-404.

Veneroni, B., and P. G. Fernandes. 2021. Fishers’ knowledge detects ecological decay in the Mediterranean Sea. Ambio:1-13.

How Recreational Fishing Videos are Aiding Management Efforts

By Nina Colagiovanni, SRC intern

As technology advances in today’s world, scientists are becoming more aware of the benefits of data gathered from platforms like YouTube. Research conducted by Sbragaglia et al. collected YouTube videos relating to recreational fishing of four species of grouper: dusky (Epinephelus marginatus), white (Epinephelus aeneus), goldblotch (Epinephelus costae) and dogtooth (Epinephelus caninus). Recreational fishing refers to any fishing activity that is not done for commercial purposes (Giovos et al., 2018).

Figure 1:  mA Fishing Rod and Reel Set Up [Wynand van Poortvliet via Unsplash]

This research was carried out in Italy between the years of 2011 and 2017 in order to understand the ecological patterns of groupers in the Mediterranean Sea and to demonstrate how data can aid in conservation science (Sbragaglia et al., 2020). Data was obtained from anglers and spearfishers who had uploaded videos of their catches publicly. 

Prior research examined recreational fishing videos of common dentex (Dentex dentex) which is an important species in the Mediterranean, and it was found that there was greater support as well as a greater mass of fish caught in angling videos versus spearfishing videos (Sbragaglia et al., 2019). 

This research focused on groupers which are currently listed under the International Union for Conservation of Nature (IUCN) Red List. Their hypothesis included that larger target species will search for protection from fishers in deeper waters, known as the “depth refuge” hypothesis (Sbragaglia et al., 2020). Additionally, they wanted to examine whether there was a northward expansion in the white grouper.

Figure 2: Number of Annual Videos Related to Recreational Fishing of Groupers [Sbragaglia et al. 2020]

A total of 2097 videos were identified over the years, with 1714 (82%) relating to spearfishing and 383 (18%) relating to angling (Sbragaglia et al., 2020). The videos were reported in regard to fishing method, which marked angling with red triangles and spearfishing with blue circles, as shown in Figure 2 (Sbragaglia et al., 2020). It can be seen that the trends differed depending on the species. For instance, the dusky, white and goldblotch groupers had more videos relating to spearfishing, while the dogtooth did not. This is due to the fact that dogtooth groupers inhabit deeper water where it is more difficult to spearfish.

In comparison to the common dentex, spearfishing videos were more representative in grouper species. This could infer that more spearfishing videos are being uploaded to YouTube or that spearfishing is a more popular method for grouper catches.

Figure 3: A Dusky Grouper [Pascal van de Vendel via Unsplash]

Overall, their results found that body mass and depth in angling videos were greater than in spearfishing videos for both the dusky and white groupers, and that there was a northward expansion of the white grouper (Sbragaglia et al., 2020). This supported their initial hypothesis, indicating that there were shifts in grouper distribution.

This research not only provides insights into the ecological patterns of groupers, but also displays how digital data gathered from platforms like YouTube can be utilized for research purposes and can contribute to management of marine species like the grouper or the common dentex in the future. 


Works cited

Giovos, I., Keramidas, I., Antoniou, C., Deidun, A., Font, T., Kleitou, P., . . . Moutopoulos, D. (2018, June 28). Identifying recreational fisheries in the Mediterranean Sea through social media. Retrieved March 10, 2021, from

Sbragaglia, V., Correia, R., Coco, S., & Arlinghaus, R. (2019, June 14). Data mining on YouTube reveals fisher Group-specific Harvesting patterns and social engagement in recreational anglers and spearfishers. Retrieved March 10, 2021, from

Sbragaglia, V., Coco, S., Correia, R., Coll, M., & Arlinghaus, R. (2020, October 04). Analyzing publicly available videos about recreational fishing reveals Key ecological and social insights: A case study ABOUT groupers in the Mediterranean Sea. Retrieved March 10, 2021, from

Behavior modifications in whale sharks (Rhincodon typus) suggest a need for tourism management intervention

By Adrianna Davis, SRC intern

The whale shark (Rhincodon typus) is the world’s largest extant fish species (Figure 1). Whale sharks are solitary animals; however, they aggregate where there is high availability of copepods, fish eggs, and crab larvae, which are staples of the whale shark’s broad diet (Legaspi et al. 2020). The elusiveness of the whale shark contributes to its popularity with tourists. Encounters with whale sharks began in 1980s at Ningaloo Marine Park and have since been adopted in other areas where whale sharks frequent. In 2018, approximately $10 million was input into the economy by the 500,000 tourists who visited Oslob, Philippines to see whale sharks (Legaspi et al. 2020). Despite economic benefits, concerns have arisen regarding the pressure this puts on whale sharks.  

Figure 1: Anterior view of a whale shark swimming at the surface (Source: NOAA 2019)

A recent study conducted by Legaspi et al. suggests that management intervention is necessary to mitigate the tourism pressure on whale sharks. The team conducted focal follow surveys in an interaction area off of the Philippines (Figure 2) from February 2015 to May 2017 to understand how external stimuli influences shark behavior. Researchers used photograph identification to record sharks’ behaviors in response to events that occurred in the survey period. The events and behaviors were previously outlined by the researchers (Legaspi et al. 2020). The collected data was analyzed using a binomial generalized linear mixed model (GLMM) to integrate variables.  

Figure 2: Map of the study site in the Philippines that magnifies into the interaction area (c) (Source: Legaspi et al. 2020)

From the 358 twenty-minute surveys that were conducted, there were 692 events recorded, including 38 active touches and 301 passive touches. Violations to regulations set by the local government included 75.1% of swimmers coming within 2 m of the shark and 13.4% of at least one diver coming within 2 m of the shark (Figure 3). These events made the sharks more likely to exhibit an avoidance behavior, which was recognized by the shark diving, swimming off, rolling back its eyes, or shuddering violently (Legaspi et al. 2020).  

Figure 3: Frequency of the number of people seen within 10 m of the sharks in comparison the recommended maximum of six (indicated by the red line) (Source: Legaspi et al. 2020)

 The whale sharks that were observed feeding were less likely to display avoidance behaviors. This may indicate that the whale sharks learned to associate food with the site (Legaspi et al. 2020). Although the learning abilities of sharks have not been heavily studied, an experiment on small-spotted catsharks (Scyliorhinus carnicula) found that the foraging efficiency of the catsharks significantly improved when food was used for positive reinforcement techniques (Kimber et al. 2013). It is possible that whale sharks in Oslob have begun to exploit the provisions of tourist boats. One concern that arises is how non-target species will be impacted by provisioning. Studies on bait and chum input from shark cage-diving have shown that nontarget species will forage on these provisions and alter their diet (Meyer et al. 2020).  

As wildlife tourism increases in popularity, the threats of overcrowding and noncompliance of visitors, as well as the implications from provisioning, will continue to negatively impact shark behavior if not properly monitored. One possible mitigation strategy is developing an assessment framework available to researchers, managers and policy makers (Meyer et al. 2021). The wellbeing of the whale shark population must be prioritized so that the species can thrive, allowing tourists to continue to have memorable experiences and local economies to thrive.  


Works Cited 

Kimber J.A., Sims D.W., Bellamy P.H., Gill A.B. 2013. Elasmobranch cognitive ability: using electroreceptive foraging behaviour to demonstrate learning, habituation and memory in a benthic shark. Anim. Cogn. 17:55-65. 

Legaspi C., Miranda J., Labaja J., Snow S., Ponzo A., Araujo, G. 2020. In-water observations highlight the effects of provisioning on whale shark behaviour at the world’s largest whale shark tourism destination. R. Soc. Open Sci. 7:200392.  

Meyer L., Apps K., Bryars S., Clarke T., Hayden B., Pelton G., Simes B., Vaughan L.M., Whitmarsh S.K., Huveneers C. 2021. A multidisciplinary framework to assess the sustainability and acceptability of wildlife tourism operations. Conservation Letters 

Meyer L., Whitmarsh S.K., Nichols P.D., Revill A.T., Huveneers C. 2020. The effects of wildlife tourism provisioning on non-target species. Biological Conservation 

NOAA, 2019. Whale shark viewing photographer [Photograph]. 

Corals and Seaweed: The Fight for Dominance

By Konnor Payne, SRC Intern

Coral reefs exist because the environment around them gives them the means to survive. These conditions are also the perfect environment for seaweeds, which compete with the corals for space. Worldwide, there have been recorded occurrences of transitions from coral to seaweed dominance. Researchers at the University of California Santa Barbara theorized that this was due to the overfishing of herbivores that would otherwise keep the seaweeds at bay, or nutrient enrichment, leading to an explosion of seaweed. To test this hypothesis, they traveled to the barrier reef of Moorea, French Polynesia. This reef had experienced an outbreak of coral-eating sea stars in the past few decades that reduced the coral cover to less than 5%. For unknown reasons, the fore reef (outer slope) has recovered but not the corals in the lagoon (back reef), which have been taken over by a seaweed called Turbinaria ornata. Investigating the difference in the corals’ resilience along the fore reef and lagoon could give insight into herbivory tipping points to maintain a coral-dominant environment. There was also a chance of “hysteresis,” or the idea that a slight change in one parameter produces an environment that requires a more significant change in the same parameter to return the environment to its original state. 

Figure 1. Adult Turbinaria ornata in Moorea, French Polynesia that compete with corals for space and resources (Schmitt, 2019).

The resilience test was conducted in the lagoon by mimicking storms’ varying intensities for 26 months on patch reefs and observing their recovery over 37 months. The researchers replicated a storm disturbance by removing all or parts of seaweed on the sample site. The researchers compared the abundance of coral at the beginning of the experiment to the end. The corals were highly resilient to a moderate disturbance, but not severe disturbance, from which they failed to recover and became dominated by turf algae. If the amount of herbivory is insufficient, the area will convert fully to seaweed dominance due to fishing pressure. 

Figure 2. The exclusion cage is placed on a patch reef to limit herbivorous fish’s body size that graze on it (Schmitt, 2019).

To test for hysteresis, a series of cages with various-sized holes were placed across patch reefs to limit the herbivorous fish body size, limiting their feeding capacity (Fig. 2). The researchers left these sites for as long as needed until the system naturally reached a stable state. The researchers found hysteresis at both sites by comparing the stable states of coral versus seaweed across the fore reef and lagoon. However, the standard conditions on the fore reef had herbivory action high enough to prevent seaweed dominance. In contrast, the lagoon is on the tipping point. The lagoon is at risk for completely transitioning to a seaweed-dominant environment, whereas the fore reef will likely remain coral-dominated. The researchers concluded that reversing an undesired shift on coral reefs would be difficult due to the hysteresis effect. The results suggest that proactive management strategies to prevent shifts in the first place will be more effective than management strategies targeted at restoration. 


Works Cited

Schmitt, R. J., Holbrook, S. J., Davis, S. L., Brooks, A. J., & Adam, T. C. (2019). Experimental support for alternative attractors on coral reefs. Proceedings of the National Academy of Sciences, 116(10), 4372-4381.

Crime on the High Seas: How Organized Crime Could Hinder a Sustainable Ocean Economy

By John Proefrock, SRC Intern

When you think of organized crime your mind probably drifts towards the mafia and cartel or the dramatized versions of these organizations that show up in TV shows and movies. So, it may come as a shock to some that there is a direct threat from organized crime to the future of a sustainable ocean economy. Organized crime in the fisheries industry isn’t a new issue, even Al Capone utilized the commercial fishing industry to smuggle rum during prohibition (Ensign, 2001), but there is a lack of awareness on the international stage to the danger that crime organizations can have on maritime industries. The goal of Witbooi et. al. (2020) is to provide the current state of knowledge on organized crime in the fisheries sector so that the information can be distributed and acted on by nations which have a vested interest in the growth of a safe and sustainable ocean economy. 

Organized crime on the sea is not as lighthearted as The Pirates of the Caribbean would have you believe. These organizations indiscriminately use illegal fishing practices to obtain copious amounts of sea life. The illegal catch is then sold on the market to unsuspecting consumers using fraudulent documentation, often undercutting the ethically sourced seafood and perpetuating the cycle of harmful practices. One example of such an operation is the case of The Viking, a ship that was detained in Indonesian waters by the Indonesian Navy. This ship was illegally catching and selling Patagonian Toothfish, Dissostichus eleginoides. The operators of the ship were utilizing illegal gillnets, the most discarded fishing equipment in the commercial sector, meaning that many end up entangling whales and other large sea fauna (Shester et. al, 2011). Use of nets over 2.5km long is punishable by 5 years in jail and a fine up to $150,000 US dollars. These fishermen also reported to a organizer who profited from the illegal sale.

A Patagonian Toothfish: Dissostichus eleginoides Source:

Aside from fisheries violations, organized crime on the ocean also encompasses fraud, money laundering, smuggling/drug trafficking, corruption and forced labor. The challenge associated with dealing with this wide variety of issues boils down to a couple main points. The first is a lack of national prioritization due to a lack of information and the difficulty associated with investigating claims of illegal activity. There is also the issue of unclear jurisdiction, or who can actually act on crime that has been observed and a lack of capacity and skillset of law enforcement to deal with organized crime on the high seas. 

A pelagic thresher shark, Alopias pelagicus, killed after getting caught in a gill net.

Positive developments in this field would include the strengthening of international cooperation to create a wide-sweeping net of jurisdiction so that no illegal operation flies under the radar, with a constant exchange of information and intelligence. Training the law enforcement agencies to deal with this specific breed of crime would also prove beneficial to the future of sustainable fisheries. These steps can ensure the future of our oceans and a sustainable maritime economy.


Work Cited:

Ensign, Eric S. Intelligence in the Rum War at Sea, 1920-1933. Joint Military Intelligence Coll Washington Dc, 2001. 

Shester, Geoffrey G., and Fiorenza Micheli. “Conservation Challenges for Small-Scale Fisheries: Bycatch and Habitat Impacts of Traps and Gillnets.” Biological Conservation, vol. 144, no. 5, 2011, pp. 1673–1681., doi:10.1016/j.biocon.2011.02.023. 

Witbooi, Emma, et al. “Organized Crime in the Fisheries Sector Threatens a Sustainable Ocean Economy.” Nature, vol. 588, no. 7836, 2020, pp. 48–56., doi:10.1038/s41586-020-2913-5.

Advances in Understanding Grey Seal Pup Behavior

By Emma Schillerstrom, SRC Intern

Grey seals are pinnipeds which inhabit the North Atlantic Ocean. They were once popularly hunted, and until 1967, grey seal numbers in the North Sea had dwindled to near absence for centuries (Peschko, et al., 2020). Today, the population counts are steadily rising, and they are protected under the Marine Mammal Protection Act (Magera, Flemming, Kaschner, Christensen, & Lotze, 2013).

Image of a grey seal pup (Jaan Minakov, CC BY 4.0>, via Wikimedia Commons).


A map of the North Sea (Halava, CC BY-SA 3.0>, via Wikimedia Commons).

After birth, grey seals wean for 15 to 18 days before their mother leaves. After, they are left on their own to undergo a fasting period followed by around 36 days of learning to forage (Peschko, et al., 2020). Researchers in Germany teamed up to investigate how grey seal pups in the southern North Sea disperse during their early stages of life (Peschko, et al., 2020). How they fare during early development determines whether they will survive past their first year of life, join the adult population, and reproduce successfully (Peschko, et al., 2020).

From 2015 to 2017, the scientists glued satellite tags to the backs of 11 grey seals found on Helgoland, a small German island in the North Sea. Each seal was a pup aged around 6 to 8 weeks. These tags provided the position of the seal each time it surfaced and paused data collection when it returned to land. The tags collected environmental data, including the water depth and distance from land, while also keeping track of temporal data, such as the number of weeks passed since the animal was originally tagged.

An aerial view of Helgoland where the seal pups were tagged (Pegasus2, CC BY-SA 3.0 <>, via Wikimedia Commons).

The researchers were able to innovatively use tag data to understand the seals’ specific behavior patterns. Behavior was assessed using a three-part classification system based on the seal’s velocity and turning angle. High velocity with a low turn angle was classified as “fast travelling”, low velocity travel with a low turn angle was considered to be “slow travelling or resting”, and high turn angle, regardless of velocity, was identified as “foraging”. The tags were removed naturally by the seals’ annual molting (Peschko, et al., 2020).

They discovered that the pups stayed close to the island for the first week before beginning to disperse along coasts. The seals remained in waters shallower than 40 meters until at least four weeks old. The frequency of foraging increased over time until week seven then decreased thereafter. This suggests that the pups hunt more frequently as they develop their skills and less frequently once they have refined their abilities and their efforts become more efficient (Peschko, et al., 2020). Additionally, the distance travelled from the island and the frequency of fast travel increased with age, likely correlated with improved swimming ability (Peschko, et al., 2020).

Characterizing their behavior and habitat use early on is crucial for assessing the population’s adaptability as well as determining what may impact its survival. Pollution, bycatch, oil spills, and heavy boat traffic pose threats to grey seals (Gray Seal Conservation and Management, n.d.). If these anthropogenic hazards occur in an area where young tend to disperse, this could prevent the seals from maturing and reproducing, rapidly sending the population toward extinction. Therefore, knowing how the young disperse allows for more-informed conservation efforts to be established.


Works Cited

Gray Seal Conservation and Management. (n.d.). Retrieved from National Oceanic and Atmospheric Administration:

Magera, A., Flemming, J., Kaschner, K., Christensen, L., & Lotze, H. (2013). Recovery Trends in Marine Mammal Populations. PLOS One.

Peschko, V., Muller, S., Schwemmer, P., Merker, M., Lienau, P., Rosenberger, T., . . . Garthe, S. (2020). Wide dispersal of recently weaned grey seal pups in the Southern North Sea. ICES Journal of Marine Science, 1762–1771.

Fishing for Answers: Learning About Fishery Research Volunteers Through Surveys

By Oliver Topel, SRC Intern

Today’s blog revolves around a group of researchers who interviewed volunteers from the California Collaborative Fisheries Research Program (CCFRP). Their paper, “Long-term participation in collaborative fisheries research improves angler opinions on marine protected areas,” examines how the volunteers’ time in the program impacts their views on marine protected areas (MPAs). The survey showed a clear relationship between time as a volunteer and perceptions of marine resource value and fishery management. 

Let’s start with a quick little history lesson, shall we? In 1999, California passed the Marine Life Protection Act, which directed the state to increase the protection of their local marine habitats, which led to several marine-focused organizations coming together under this unifying law, and in 2006 the CCFRP was created. The California Collaborative Fisheries Research Program monitors groundfish populations, such as rockfish, groundfish, skates, and rays. It uses the data collected to make future predictions of species diversity and catch rate. According to the article, “Between 2007 and 2016, CCFRP annually surveyed four sets of MPAs along the central coast including Año Nuevo State Marine Reserve (SMR), Point Lobos SMR, Piedras Blancas SMR, and Point Buchon SMR” (Mason et al., 2020).  

While the benefit of the CCFRP is more than evident, what’s not as clear-cut as the volunteers’ perception of the work they do. This where the survey comes in. To conduct this experiment, the researchers distributed a 29-question survey to 722 volunteer anglers in CFRP. The survey consisted of several different types of questions, such as multiple choice and ordinal scale. They were distributed through email in the Spring of 2018 (Mason et al., 2020). The questions themselves ranged from being about CCFRP, MPAs, and personal demographic data about the individual taking the survey. Despite so many recipients, only 15% of the volunteers completed and sent in their survey. A majority of the responses were positive, with volunteers not only believing that the CCFRP is a beneficial organization but that they have learned from and contributed to the work the organization does. To learn more about these results, you can look at Figures 2-4 below.  

Figure 1: From Mason et al. (2020, pg. 2): “Marine Protected Areas in central California monitored by CCFRP between 2007 and 2016”


Figure 2: From Mason et al. (2020, pg. 15): “Predicted probability of CCFRP volunteer anglers having an opinion change on MPAs relative to time”

Overall, this article portrays who CCFRP volunteers are and how they have been affected by the program. Results show that positive change in opinion became significant after an extended time with the program (sometimes up to 7+ years) (Mason et al., 2020). Hopefully, this article, and maybe even this blog, encourages people to volunteer with programs such as the CCFRP and put some real-time in, and you might even have a change of viewpoint.


Work cited

Mason ET, Kellum AN, Chiu JA, Waltz GT, Murray S, Wendt DE, Starr RM, Semmens BX. 2020. Long-term participation in collaborative fisheries research improves angler opinions on marine protected areas. PeerJ 8:e10146. DOI 10.7717/peerj.10146

Genomic vulnerability of a dominant seaweed species points to future-proofing pathways for Australia’s underwater forests

By Rebecca VanArnam, SRC Intern

Endemic to Australia, Phyllospora comosa “is a forest-forming seaweed inhabiting the south-eastern Australian coastline that supports vital ecosystem functions” (Wood, 2021) (Figure 1). Like other species, climate change is causing biological changes within seaweed and seaweed-dependent organisms (Wernberf, 2011). As climate change impacts this seaweed species in Australia, scientists look to find adaptation patterns that the organism may possess. An organism’s genome can be assessed and used to understand how organisms adapt to changing environments.  

Figure 1: A photograph providing an image of Phyllospora comosa at a restoration site. (a) Represents an area that was restored (b) represents donor Phyllospora comosa to the area. [Image source: Coleman, 2017]

The increasing destruction caused by climate change influences scientist’s to perform research and look to find possible solutions while using marine genomics to do so. “Seascape genomics” became a popular tool to assess the seaweed species, Phyllospora comosa, within this study that took place in Australia. Seascape genomics evaluates a species’ spatial movement and dependence on environmental factors, such as climate change, and what role that dependence plays in the structure of an organism’s genomic patterns (Liggins, 2019).  In this study, genetic turnover was measured against sea surface temperature allowing for the further understanding of which genes within Phyllospora comosa are more vulnerable to changing temperatures (Wood, 2021). 

The analysis found that the Phyllospora comosa have relatively high gene flow, which means that their genetic material passes from one population to another, connecting their generations. The results also showed that genetic diversity was lower close to the edges of the species’ range. When linking these results to future climate change and fluctuating temperatures, it became evident that ocean warming is a definite threat to the populations where local adaptation is most likely occurring (Figure 2). This causes the central range, where diversity is highest, to be recognized as the most vulnerable area for the Phyllospora comosa (Wood, 2021).

Figure 2: A close-up photograph of the complexity of Phyllospora comosa [Image source: Wikipedia/ Phyllospora comosa]

Overall, the genetic methods used to analyze this data need to be used further to model patterns that can be developed and used to describe “genetically desirable populations” to protect this critical endemic seaweed. Not only are these methods needed for Phyllospora comosa, rather they have become and should continue to become understood and used as essential resources to help reduce climate change effects (Wood, 2021). 


Works Cited: 

Coleman, M. A., & Wernberg, T. (2017). Forgotten underwater forests: the key role of fucoids on Australian temperate reefs. Ecology and Evolution, 7(20), 8406-8418.

Liggins L., Treml E.A., Riginos C. (2019) Seascape Genomics: Contextualizing Adaptive and Neutral Genomic Variation in the Ocean Environment. In: Oleksiak M., Rajora O. (eds) Population Genomics: Marine Organisms. Population Genomics. Springer, Cham.

Wernberg, Thomas, et al. “Seaweed Communities in Retreat from Ocean Warming.” Current Biology 21.21 (2011): 1828-32. Print.

Wood, Georgina, et al. “Genomic Vulnerability of a Dominant Seaweed Points to Future‐Proofing Pathways for Australia’s Underwater Forests.” Global Change Biology (2021). Print.