Laugan Miller

Jim Spickard

Research Methods

4/7/19

Stability of Sea Urchin Dominated Barren Grounds Following Destructive Grazing of Kelp in St. Margaret’s Bay, Eastern Canada

The regrowth of kelp forest was observed in St. Margaret’s Bay in Nova Scotia Canada. This area had had no macroalgae for several years but was starting to see some regrowth. Within 10 months sea urchins had wiped out the regenerating kelp forests. There was also experimental kelp that was destroyed as well. This report says that in an area, even at the lowest biomass of sea urchins, regeneration of kelp forests seems unlikely. There were two questions looked at in this research. The first question was would the newly regenerating sporophytes become reproductive and re-establish mature forest? The second question was regeneration occurring on a wide scale in St. Margarete’s Bay? The research showed that no new kelp was able to grow because it was all consumed by sea urchins. While I want to look at how predators can affect sea urchin levels resulting in less kelp deforestation I think it is also important to look at if its possible for kelp forests to regrow with any sea urchins around. This research showed that even if there is some regrowth of kelp forests sea urchins are able to wipe them out before they grow big enough. This made me interested in a follow up question to my research question of how long it would take kelp to grow big enough that sea urchin levels wouldn’t have as big of an effect. With this, how hard would it be for humans to manage this.

Chapman, A. R. O. “Stability of Sea Urchin Dominated Barren Grounds Following Destructive Grazing of Kelp in St. Margaret’s Bay, Eastern Canada.” SpringerLink, Springer-Verlag, link.springer.com/article/10.1007/BF00397697.

Laugan Miller

Jim Spickard

Research Methods

3/31/19

Killer Whale Predation on Sea Otters Linking Oceanic and Nearshore Ecosystems

This research looks at the relationship between sea urchins, sea otters, and killer whales in Alaska. This was important to look at because recently sea otters have been declining in Alaska. The birth rates of sea otter’s in these locations is equal to that of sea otters found in stable environments. This means there must be increased mortality rates to justify the declining populations of sea otters. Researchers ruled out migration because there were no new sea otter populations and ruled out disease because this would have been seen by dead carcasses washing up on the beach. The research looked at three key points of evidence leading to their results which was that the decline in sea otter populations was due to increased predation on sea otters. Calculations showed that this otter decline could have been due to just 3.7 whales. The most likely shift of killer whales preying on sea otters is due to the killer whales losing a prey item. Some prey items of killer whales include stellar sea lions and harbor seals and these species have both had a decline in populations since the 1970s. The relationship between sea otter populations and the collapse of kelp are most likely caused by the offshore oceanic realm. This changed the system from a three level trophic system to a four level trophic system which means sea otters were no longer the top predator. This freed sea urchin populations to expand. This article was helpful to my research because I know that I not only have to look at possible predators of sea urchins but their possible predators and what would cause them to shift to eating sea urchins.

Estes, J. A., et al. “Killer Whale Predation on Sea Otters Linking Oceanic and Nearshore Ecosystems.” Science, American Association for the Advancement of Science, 16 Oct. 1998, science.sciencemag.org/content/282/5388/473.

Laugan Miller

Jim Spickard

Research Methods

3/24/19

Causes and consequences of sea urchin abundance and diversity in Kenyan coral reef lagoons

This research takes place in Kenyan Coral reef lagoons. The purpose of this study was to look at the main predators of sea urchins, the effect of predation on sea-urchin community structure, and the effect that an increase in sea urchin populations as well as a decrease in finfish populations would have on lagoonal substrate. This research looked at 6 different reef sites, two of which are protected. At these reefs, fish and sea urchin abundance was looked at as well as other factors. Finfish populations we 4X denser in protected areas and sea urchins larger than 100X denser. predation rates on sea urchins were 4 times lower in unprotected reefs, because their predators were not protected and were being fished. But then the artile said Balistad was the only fish that had a higher population in protected areas than in non-protected. Balistad populations were negatively correlated with sea urchin populations. The decrease in top invertebrate eating carnivores had a negative effect on the entire ecosystem of the coral reef. I would like to get the full document to look at how this reflects on other coral reefs with sea urchins and the relationship between top predator populations and sea urchin populations.

McClanahan, T. R., and S. H. Shafir. “Causes and Consequences of Sea Urchin Abundance and Diversity in Kenyan Coral Reef Lagoons.” SpringerLink, Springer-Verlag, link.springer.com/article/10.1007/BF00317561.

Laugan Miller

Jim Spickard

Research Methods

3/19/19

Overfishing reduces resilience of kelp beds to climate-driven catastrophic phase shift

In Tasmania coastal waters are warming approximately 4 times higher than the average elsewhere. This has led to an increase in sea urchin levels which are causing deforestation of kelp beds and loss of biodiversity. These sea barrens are especially predominet in areas where fishing has wiped out sea urchin predators, specifically lobsters. The point of this research was to look at if areas in Tasmania with increased rates of fishing effected have a negative impact on the resilience of kelp beds and increase the amount of overgrazing by C. rogers a long-spined sea urchins. To test this theory, C. rogers were put in to reefs in Tasmania where there are no-take MPAs with large amounts of and other reefs that have open fishing and have low levels of sea urchin predators. In Australia C. Rodgers has had the highest damage of shallow reefs. The results showed that sea urchins were not able to grow their numbers as large in areas where there predators were present. It was also important that lobsters were large enough to be able to wrap around the sea urchins which is not found in most areas with fishing.

Ling, S. D., et al. “Overfishing Reduces Resilience of Kelp Beds to Climate-Driven Catastrophic Phase Shift.” PNAS, National Academy of Sciences, 29 Dec. 2009, www.pnas.org/content/106/52/22341.full.

Laugan Miller

Jim Spickard

Research Methods

2/10/19

A Plague Of Delicious Purple Urchins Is Taking Over The California Coast And It’s Our Duty To Eat Them

A newer solution to the increased sea urchin populations is to use the often looked down upon even larger hungry population of humans ready to jump on new trends. In just the past four years 90 percent of the coastal kelp in San Francisco to Oregon has been removed mainly due to the 6,000 percent increase in purple sea urchins. Last year the CDFW stopped recreational abalone fishing due to the lack of kelp forests leaving no food for the abalone and causing a dive in population number. This method of using the sea urchins as a source of food for humans was able to reduce many sea urchin barrens that had been around for a long time in the late 19^th century. Purple urchins are small and only get to around 3 or 4 inches but what they hold on the inside can be used in many different ways.  I think this article is amazing because it really shows that more people than just scientists can combat environmental problems and in so many unique ways. In addition, the demand for hunting and collecting will hopefully result in availability of jobs. To take this farther I would look at how many restaurants are putting sea urchins into their menus and people’s responses.

Bouzari, Ali. “A Plague of Delicious Purple Urchins Is Taking Over the California Coast and It’s Our Duty to Eat Them.” SAVEUR, www.saveur.com/sea-urchins-in-mendocino#page-8.

California mobilizes to save invaluable kelp – will efforts be vain?

California’s north coast used to be covered in a bull kelp forest creating a safe ecosystem for fish and other organisms to grow. Four years ago an epidemic wiped out the sunflower sea star leaving the purple sea urchins without their main predators and freedom to graze on kelp and grow their population. Today this once thriving ecosystem is known as an “urchin barren” because it is only inhabited by purple sea urchins and not many other marine animals. This problem is still made worse by the fact that kelp forest are unable to thrive in the growing temperatures of the ocean making growing these forests back even more difficult. Normally sea otters are unable to keep sea urchin populations low but that is not what they are seeing in Monterey.  One solution to this problem is sending kayaks and boats out with a giant vacuum and sucking up the urchins and then turning them into compost. Some places have used hammers and gone around smashing urchins but there is currently a law against doing this. To take this further I would look more into this law and see what it is protecting and how reversing it could benefit or harm the ecosystem. Also looking at how if there are sea otters in the area the population of sea urchins still continue to grow? Is it worth looking at efforts to bring back the sunflower sea star?

Bland, Alastair. “California Mobilizes to Save Invaluable Kelp – Will Efforts Be in Vain?” Oceans, News Deeply, 9 Apr. 2018, www.newsdeeply.com/oceans/articles/2018/04/09/california-mobilizes-to-save-invaluable-kelp-will-efforts-be-in-vain.

Laugan Miller

Jim Spickard

EVST Research Methods

2/18/19

Effects of predators on sea urchin density and habitat use in a southern California kelp forest

Kelps form the base for many ecosystems by providing safe places for prey to hide. Sea urchins are disturbing these kinds of ecosystems by preying on the kelps. Researchers wanted to look at the possible effects of predators consuming the sea urchins and dropping their population numbers to stop kelp deforestation. While normally sea otters prey on urchins this research looked at an environment with sheepheads and lobsters as top predators. In this ecosystems the predators had to be a certain size in order to break the sea urchins apart which then prompted smaller predators to eat the scraps. This means that even though there might be an area with a heavy population of predators only a few can prey on the urchins and so they probably wouldn’t be able to control their population levels. This lead to researchers observing that urchin mortality rates were lowest were urchin populations were highest. These predators are unable to control the population of sea urchins. What to look at next would be what is limiting these predators sizes like overfishing and what introducing other predators would do to the ecosystems. What could also be helpful is other strategies that researchers have found worked to reduce sea urchin population sizes.

Nichols, Kathryn D., et al. “Effects of Predators on Sea Urchin Density and Habitat Use in a Southern California Kelp Forest.” SpringerLink, Springer, 24 Apr. 2015, link.springer.com/article/10.1007/s00227-015-2664-2.

Laugan Miller

Jim Spickard

Research Methods

2/11/19

“Building Sustainable Groundwater Management in California”

The sustainability ground water act has formed agencies to bring water basins up to a higher standard in California. This is an important article because what happens to the water inside of a state can affect the water in our oceans. Drilling of wells to find more water has increased because of the drought California is experiencing which has had such a huge impact that the water table is lowering. Ground water makes up slightly less than fifty percent in normal years and more than fifty percent of water to cities and farmers in years when droughts are occurring. One of the proposed solutions is to collect groundwater and put it into a basin which can be used if it is a drought year. I thought this article might relate to my topic because it would give me a better understanding of some of the issues we are dealing with water management. To take it further I think it would be interesting to look at how creating more water environments would affect the water table. From this we could look at the effect of water not being able to run off into the ocean and see if it is a negative or positive effect on coastal ecosystems. Also the article brought up salinization of when the water table becomes lower than that of the ocean’s and our water gets saltier.

Pitzer, Gary. “Now Comes the Hard Part: Building Sustainable Groundwater Management in California.” Water Education Foundation, www.watereducation.org/western-water-magazine/now-comes-hard-part-building-sustainable-groundwater-management-california.

“Bioeconomies of scope and the discard problem in Multiple-species fisheries”

This case study was very important to look at because it not only looked at what fish should go into fisheries but also incentives to prevent fishermen from throwing bycatch overboard. In the U.S. it is estimated that nearly 22% of what is caught is bycatch. The article talks about biological decline and the irreparable damage we are doing to these ecosystems by taking away species that play vital roles in their ecosystems. They discuss the importance of using the design of an ecosystem in fisheries, with many interactions between different species. One example of a design for fisheries was to use a prey and predator pair of fish in fisheries. This way when prey populations increase so does the population of the predator colony. This will help insure that fish populations stay high and create a more natural environment for the fish. The second aspect of this article was how to stop fishermen from wasting fish and make it more beneficial for them to keep bycatch. The original approach is to have an observer on board the boats to watch over what is being thrown out. Another strategy is the sole owner harvest policy. I didn’t completely understand how this worked but it is meant to eliminate fisherman seeing the extra species they catch as undesirable. Having this plan in place would stop overfishing because people would be satisfied with the amount of fish caught.

Singh, Rajesh, and Quinn Weninger. “Bioeconomies of Scope and the Discard Problem in Multiple-Species Fisheries.” Journal of Environmental Economics and Management, vol. 58, no. 1, 2009, pp. 72–92., doi:10.1016/j.jeem.2008.08.005.