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California is a pretty amazing place for many reasons, and one is that we have a lot of different species and subspecies of salmon! The Sacramento River, for example, is the only major river in the world that has four distinct subspecies, or runs, of Chinook Salmon!

Salmon are such amazing creatures! They are so important to the ecosystems in which they live, and they have been so important to human societies for so long that they get a lot of attention, and rightly so. And, when their populations are not doing well, ecosystems and human societies feel the impacts.

Two adult Coho Salmon migrating up a river. Photo: U.S. Fish and Wildlife Service.

Coho Salmon (Oncorhynchus kisutch), sometimes called Silver Salmon, are one of the species found in California. They are a species that live in the ocean for most of their lives, but then migrate up rivers and streams along the north and central coast of California to breed and lay their eggs in gravel beds in the upper watersheds. In addition to being found in California, Coho Salmon are also found breeding in rivers and streams along the Pacific coast of North America all the way to Alaska, and the Pacific coast in northeastern Russia as far south as northern Japan.

When they do this epic migration, how long it takes, where they lay eggs, how long those eggs take to hatch, what the young salmon need to survive and for how long, when the young salmon migrate down river and into the ocean, and how long they live there before returning to the river of their birth are all important aspects of Coho Salmon biology that need to be understood if restoration efforts are to be successful.

The grant program I manage funds salmon recovery projects, so I am writing this blog post in part to help myself understand the life cycle of the Coho Salmon so that I can make the best decisions I can when deciding what projects to fund. So, with no further adieu…

The Coho Salmon life cycle in California:

In January, adult female Coho Salmon will lay between 1,500 and 3,000 eggs each in a gravel nest, called a redd, in a stream in the upper watershed of a river system. After mating and laying eggs, the adult Coho die (more on this later).

Many of the eggs are eaten by other aquatic animals, but generally between 200 and 300 hatch. This takes between 50 and 70 days depending on water temperature.

A stream in the upper Navarro River watershed in California where young Coho Salmon spend a bit over a year feeding and growing. Photo: A Birding Naturalist.

Once they hatch, these young Coho Salmon spend approximately a year living in shallow areas of streams where they can hide amounts rocks and large woody debris and prey on smaller fish and aquatic insects.

After about 14 months living and growing in these shallow streams, the 50 to 100 surviving young salmon, that are now called smolts, begin to migrate down stream in spring. Their color changes. They loose the bars and spots that helped them to camouflage in the upper watershed streams and turn onto a bright silver color. Internal changes also occur with their gills and kidneys transitioning to be able to survive in salt water.

Once they reach the ocean in summer, the smolts spend about a year-and-a-half feeding and growing into adult salmon. Adult Coho commonly grow to about 18 lbs in weigh and 24 to 30 inches in length.

Beginning in December, the now three year old Coho Salmon begin their migration back up the rivers and streams. This first involves a transition period to allow their gills and kidneys to transition back to tolerating freshwater. The adult Coho also start to become more and more red in color as they migrate up the rivers. Once the adults are accustomed to freshwater, they begin swimming upstream, guided by scent and triggered by stream flow volumes, back to the upper watershed streams where they hatched.

Then in January, the one to four adults that have survived all the way to this point from all those eggs that were originally laid find a partner, mate, the females lay between 1,500 and 3,000 eggs each in a gravel nest, called a redd, and then the adults die. Unlike some other salmon species, Coho Salmon breed one time and then die. No adult Coho preform a return migration to the sea.

While the completion of the life-cycle of a Coho Salmon with the laying of eggs and death is the end of the individual salmon’s life, it is just the beginning of the lives of many other organisms and has effects that ripple out across the ecosystem. The dead adult salmon are important food sources for aquatic animals (such as crayfish, caddisflies, and rainbow trout) and terrestrial animals (such as bear, river otters, raccoons, and eagles). The decomposing adult salmon bring nutrients from the ocean in the form of their own tissues, and deposit those nutrients in mountain streams and rivers. In this way, they serve as an important source of nutrients, basically fertilizing the soils of the forests of the upper watersheds.

Coho Salmon are amazing animals with an amazing life story. I am very happy to be doing work that will help to provide the habitats and water they need to allow them to continue it to the next chapter.

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An adult Spotted Lanternfly. Photo: Wikipedia.

Are you a fan of apples, beer, maple wood furniture, or peaches? The plants that produce these products, and many more species, are at risk from a threat that is spreading across North America. What is this threat? It is a rather beautiful insect call a Spotted Lanternfly (Lycorma delicatula).

The Spotted Lanternfly was first detected in North America in 2014 when a few were spotted in Pennsylvania. Between 2014 and today, they have spread to 11 more states and are now also found in Connecticut, Delaware, Indiana, Maryland, Massachusetts, New Jersey, New York, North Carolina, Ohio, Virginia, and West Virginia.

This insect, which is not actually a fly but rather a species of planthopper, is native to China, but has spread to Japan, South Korea, and the USA and is becoming a significant agricultural pest in these other countries.

In its native China, this species is not a major issue because its population is generally kept in check by several species of parasitic wasp that feed on the Spotted Lanternfly. However, these wasps are not present in the new areas the lanternfly has spread to which has resulted in their population increasing and spreading rapidly.

Spotted Lanternfly egg mass. Photo: Rutgers University.

Spotted Lanternflies do not fly long distances on their own, so adults do not disperse very far. However, the species is very effective at dispersing via their eggs. Adult Spotted Lanternflies lay their egg masses on all sorts of objects from trees to houses to vehicles. They can even end up getting scrapped off of these structures and stuck to shoes and clothing. in this way, egg masses can be transported long distances and so introduce the species into new areas rapidly.

Luckily, the Spotted Lanternfly poses no direct threat to humans or animals. However, they suck the fluids from many species of plant which can weaken an kill them. Many of these plant species are of significant economic value, and many more create extensive and important habitat for countless other animals, plants, fungi, etc. The list of plant species that are susceptible to Spotted Lanternfly infestations includes: Almonds, Apples, Apricots, Cherries, Grapes, Hops, Maple Trees, Nectarines, Oak Trees, Peaches, Pine Trees, Plums, Poplar Trees, Sycamore Trees, Walnut Trees, and Willow Trees.

Spotted Lanternfly life cycle stages. Photo: spottedlanternflykillers.com

Control efforts are underway, and extensive help from all of us will be needed to stop the spread of this insect. The state of Pennsylvania has even step up a hotline number to call and report sightings which is 1-888-4BADFLY. Control efforts include taking extra care to clean objects that could have egg masses attached to them. This is particularly important for anything passing through areas of known Spotted Lanternfly infestations. We should all make sure to clean our cars, boats, trailers, tents, clothing, shoes, and other materials if we are moving them from or through any of the above states. Without serious control efforts, the Spotted Lanternfly is predicted to continue to spread and is likely to reach California around 2033.

If you do find adult Spotted Lanternflies it is recommended that they be killed. They are fast, so we will all have to work on our reflexes. If an egg mass is found, scrape it off and put it into a sealed plastic bag with hand sanitizer (good thing we all have this around so much these days!).

So, keep your eyes open for this insect, help control their population and spread, and report any sightings! In this way we can all help to protect our forests and farms.

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A flock of Mallards lifting off of a pond. Photo: U.S. Fish and Wildlife Service.

Each spring since 1948 staff from the California Department of Fish and Wildlife have conducted a survey of central and northeastern California to count the numbers of ducks and geese that are breeding in those areas. These counts are conducted by biologists flying in fixed-wing aircraft over the central and northern parts of California, and they form the basis of the California Breeding Waterfowl Survey. This long term data set is hugely powerful when scientists are looking at long term trends in populations and examining the effects of habitat loss, climate change, human population growth, pollution, and other factors.

Fixed-wing plane used during a breeding waterfowl survey over the Klamath River Basin. Photo: Keith Stein

The 2022 California Breeding Waterfowl Survey was just released and it’s not great. The total number of waterfowl breeding in California has declined 19% since 2019. All species were found to be in decline to some extent. Canada Goose were the least impacted with declines of 5% since 2019. Cinnamon Teal were hit the hardest with declines 54% since 2019. That means that there are only about half as many Cinnamon Teal breeding in California today as there were just four years ago! Mallard (the most common species of duck that breeds in California) and Gadwall were also hit hard with declines of 25% and 31%, respectively, since 2019.

These declines are in large part likely due to poor breeding habitat conditions. Ducks and geese need water to breed. The 2021-22 winter in California had below average precipitation across California, and the snow pack water content in California’s mountains is also below average. Such continued and serious drought conditions are resulting in less water for both natural and managed wetlands, and so to the poor breeding habitats and reducing waterfowl populations found in the survey.

Hopefully more water will fall in the state this coming winter. In the mean time, save water any way you can! The less water we all use, the more will remain in rivers, streams, reservoirs, etc. that can benefit the birds, fish, and other wildlife of California!

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Cover of The Intersectional Environmentalist by Leah Thomas.

I just finished a book called “The Intersectional Environmentalist: How to Dismantle Systems of Oppression to Protect People + Planet” by Leah Thomas. This book just came out in 2022, and it is a very interesting read. The book lays out many compelling connections between the environmental movement and social justice. It explains how BIPOC individuals and communities have, and still are, being burdened with the majority of environmental costs from pollution to climate change to food insecurities. It also does a very good job of explaining some of the history of the environmental movement and the feminist movement, and it shines a light on where and how both of these movements have a history of excluding and further marginalizing already marginalized groups.

The book also explains how inequalities play out in particular industries such as the green energy and the clothing/fashion industries. This subject is especially difficult because the overall ends may be important to pursue (transitioning to more sustainable sources of energy, for example), however we as a global society must be aware of both the ends and the means matter. If noble ends are accomplished using morally questionable means, the side effects of those means will tarnish the ends and their nobleness will be diminished. To learn more about this book and intersectional environmentalism, I highly recommend the book and the website that has tons of resources.

One specific resource that I was particularly interested to learn about was a mapping tool that has been developed by the U.S. Environmental Protection Agency (EPA) called EJScreen: the Environmental Justice Screening and Mapping Tool. This is a site that has many different layers of data that you can add on or take off a map of any area in the USA. These layers include information about pollution (such as lead paint locations, ozone rates, air particulate concentrations, etc.), socioeconomic indicators (such as race, household income rates, age demographics, etc.), health disparities (such as life expectancies, heart disease, and asthma), climate change (such as wildfire risk, sea level rise impacts, flood risks, etc.), critical services gaps (such as broadband gaps, food deserts, and lack of medical coverage) and more.

This tool allows the EPA to better understand the issues facing the country and to better fulfill their mission to protect the people and natural resources of the USA. It also allows each of us to do some exploring ourselves.

By adding or taking off layers, we can look at what factors are impacting the communities we live in. Are there areas of my city that have unusually high levels of air pollution? I can click on that data layer and see how air pollution concentrations differ across the city. Are there areas of my city for which flooding is an unusually high risk? I can click on that data layer and find out. Are there areas of my city that contain a large number of BIPOC households? I can click on that data layer and find out.

And, of course, even greater power comes from this tool when several layers are overlapped on top of each other. That is when the intersectionality of these different factors comes to light. Are the areas of high air pollution similar to the areas where large numbers of BIPOC people live? Do the areas of high flood risk overlap extensively with the areas of low income households are?

When several of the data layers are combined, distinct differences in living conditions can be made visible. And once they are viable, we can all start to figure out how to address them.

If you read this book, let me know in the comments what you think. If you play around with the EPA mapping tool, let me know if you find any interesting/surprising/disturbing correlations.

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Something that annoys me is when a group will not recognize when there own members mess up and turn a blind eye instead of holding them accountable. It makes me think that the members of a group are more concerned with defending the group rather than defending what is right (however you might define that).

So, to make sure I do not fall into that trap, I have some thoughts on the resignation of Eric Lander who was appointed by President Biden as the Director of the White House Office of Science and Technology Policy. But first, some background.

Lander was sworn in to this post on June 2nd, 2021. The mission of the Office of Science and Technology Policy is to “maximize the benefits of science and technology to advance health, prosperity, security, environmental quality, and justice for all Americans.” However, significant complains started to accumulate about Lander’s behavior and conduct toward the staff of the Office of Science and Technology Policy who worked under him. These complaints led to an internal White House investigation.

The two month long internal investigation into Lander’s behavior ended in January 2022 and “found credible evidence of instances of multiple women having complained to other staff about negative interactions with Dr. Lander, where he spoke to them in a demeaning or abrasive way in front of other staff.” It further found that Lander created a toxic work environment for many subordinates regardless of gender.

This investigation was reported on by Politico. After the Politico piece came out, Lander issued an apology via email to the staff of the Office of Science and Technology Policy. A few days after that apology, and after further pushback from current and former staff and the press, Lander submitted his resignation on February 7, 2022.

My thoughts are that it was inappropriate for Lander to resign. He should have been fired.

I think it is telling that Lander only issued his apology email after the Politic article was published. To me this suggests that it was simply done in an attempt to limit damage, and not as a genuine indication of remorse. I think there is no place for the type of toxic workplace that he seems to have engendered, and individuals who behave in such a way should be held accountable and removed from their positions, particularly when they occupy positions of power. And I think this internal investigation was only the tip of the iceberg. Lander had caused some disturbances when he dismissed the accomplishments of two fellow geneticists who contributed significant work to advanced gene editing research that Lander was involved with; surprise surprise, those two geneticists were women. And Lander has been a long standing admirer of James Watson who co-discovered the structure of DNA, and who also was well known for holding many sexist and racist views.

Has Eric Lander done some very important science? Absolutely. Did he help to advance science policy and the public understanding of science? Definitely. Does this mean he is above reproach? No way.

All in all, I don’t think Lander should have been appointed to the position in the first place. He had enough of a track record of morally dubious views that his should have been eliminated during the vetting process. And I definitely think that having him no longer in that position of power is a step in the right direction.

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E.O. Wilson, 'Darwin's natural heir,' dies at age 92
E. O. Wilson examining a leaf. He advocated for a world where all species have the space and resources to survive. Photo courtesy of National Geographic.

E. O. Wilson died yesterday at the age of 92. The sciences of entomology, biodiversity, biology, ecology, and evolutionary biology have suffered a huge loss. Beyond those specific scientific disciplines, the world has lost an amazing science communicator and advocate of nature.

Edward Osborne Wilson was born in Birmingham Alabama, USA on June 10th, 1929. He grew up chasing snakes and birds and insects around Birmingham, Washington D.C., the various other towns he grew up in (his parents were divorced and each moved several times during his childhood) and also on the many hiking and camping trips he took into the surrounding areas. This early interest in the natural world solidified into an obsession with ants which he studied throughout his undergraduate and graduate work.

In his early career, E. O. Wilson worked with another scientist named Robert MacArthur to develop a way of explaining why species tend to be scattered across the planet in the patterns that we see. Originally, these two focused on explaining, with mathematical equations, why and to what extent big islands have more species than small islands, and islands close to continents have more species than remote islands. This set of concepts became known as Island Biogeography. It was quickly recognized as having much wider applications. Not only did it work for islands, but for other features as well. Lakes could be seen as ‘islands’ set in land masses. And even further, nature preserves could be seen as ‘islands’ set in inhospitable and highly modified landscapes. Island biography can be used to predict how large a nature preserve is needed to save a certain number of species. It can be used to determine how far apart nature preserve ‘islands’ can be and still maintain viable populations of animals, plants, and fungi.

On top of island biogeography, E. O. Wilson pioneered work in sociobiology by exploring how behaviors of insects and behaviors of humans and other vertebrates are similar in many ways. He popularized the term biodiversity and spent considerable effort in working toward the preservation and documentation of life on this planet.

E. O. Wilson was also a tremendous writer. His list of written works includes over 30 books and 430 scientific articles, and these span a range of scientific and popular science material. He made scientific topics accessible to a wide range of public readers and inspired countless people (including myself) to pursue these topics further. His book “Letters to a Young Scientist” is one of the best and most inspiring books I have ever read.

Without a doubt, Wilson was a giant in the field. He developed really impactful ideas. He mentored a huge number of other scientists. To popularized science to the wider world.

We have all lost a treasure.

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I just finished a book called “Charles Darwin’s Barnacle and David Bowie’s Spider: how scientific names celebrate adventurers, heroes, and even a few scoundrels” by Stephen B. Heard.

Book cover of “Charles Darwin’s Barnacle and David Bowie’s Spider.” Photo credit: Amazon

The book is a good one with a lot of perspectives on the scientific naming the species and the stories those species names carry with them. The particular focus of the book is on species that have been named for people and what the stories of those people are, and how they came to have species named after them. There are some interesting reasons to name a species after a person. One is because that person is who collected the specimen that was later recognized as a new species. Another is as a way of honoring someone for an accomplishment. This can be a scientific accomplishment, but as the title of the book indicates, this can be any type of accomplishment (such as being a rock icon like Bowie).

The book highlights and discusses some of the positive outcomes that can occur when a species is named after a person. For one, the person giving the name can explain why they are giving a particular species a particular name and this can help to tell a story about someone. These stories help to immortalize both the person doing the naming, and the person who’s name is used in the description of the new species (it is considered very bad form for a scientist to name a species after them self, so there are just about always at least two people involved in naming a species).

But these perspectives are not enough to change my mind on this subject (I have written about issues with the naming if species a few times such as here and here). I think that naming species after people is too problematic. It opens too many avenues for bias and prejudice (conscious or unconscious) to come into play.

And the book actually adds a new way for the naming of species after people to become a problem, and that involves money. In one chapter of the book, Heard discusses how the naming of a species has been used to raise funds for various causes. How this has worked in the past is that a new species is described, that new species needs a name, and the researchers who are describing it auction off the name in order to raise money for a cause or organization.

Now, on the surface of it, I have no problem with this. What a great thing to happen, right? A person or company pays a significant chunk of money in order that a researcher names a species however the person or company wants, and then that money goes to supporting conservation and research. Terrific.

But who is going to have the money to spare to buy these species names? Wealthy people and companies. Since the majority if wealthy people are white (at least in the USA) and the majority of wealthy companies are lead by white people (at least in the USA), this practice will tend to increase the representation disparities that already exist in species names.

Paying for the privilege of naming a species just results in more white people controlling what we call things, and in being recognized in the names themselves.

While the pool of people that species are being named after is slowly growing to be more diverse with women, people of color, and members of the LGBTQ+ community starting to have their contributions to science recognized and having more species named after them, this is a very slow process indeed. And it is in the face of a centuries-long head start that white men have had. With this ongoing lack of representation in the names of species, having yet another way to shift the names of species toward white people does not seem like the right direction to me.

Surely we can find other ways to encourage people and companies to contribute to conservation and research. Surely we can name species without contributing to this example of institutional racism and lack of diversity.

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The Point Blue Conservation Science Rich Stallcup Bird-a-thon is back, as are the Drake’s Beach Sanderlings! Well, in some ways we never went away, but in 2020 the whole event was transformed into a virtual bird-a-thon with teams going out birding, but the team members birding in different locations due the inability to gather in groups because of COVID-19. Sanderlings members did participate in the event, and birded various sites in the bay area and West Sacramento.

But now that is over (hopefully). Teams will be able to meet again and head out to bird and raise funds for Point Blue Conservation Science.

As a member of the Bird-a-thon Steering Committee, I helped to organize the bird-a-thon and helped to choose the mascot bird this year: the Pine Siskin. We choose this species to highlight for a few reasons. One is that it is a generally underappreciated species. As you can see in the image above, the Pine Siskin is not an obviously flashy bird. But, to quote the new Hansen’s Field Guide to the Birds of the Sierra Nevada when noting that the perched bird can be on the drab side, “Taking flight, however, it changes from somber to eye-catching.” This striking change is due to the yellow patches in wing and tail that are generally concealed when at rest, but which flash dramatically when in flight. A second reason to highlight the Pine Siskin is that this species was hit hard by the salmonella outbreak in California that occurred in the winter and spring of 2021. This disease killed individuals of several finch species, but siskins seemed particularly susceptible. A third reason are the fires burning across California. The Pine Siskin is a finch that breeds in the conifer forests of North America. As such, they have lost a lot of breeding habitat in California this summer with so many fires burning through the conifer forests of the Sierra Nevada.

The Drake's Beach Sanderlings
The 2019 Drake’s Beach Sanderlings team standing on Drake’s Beach in Marin County.

So, in support of the Pine Siskin and the work of Point Blue Conservation Science, the Drake’s Beach Sanderlings are once again asking for your support when we head into the field to race across Marin County to find as many species as we possibly can in one day (September 26, this year). As usual, this will be a face-paced day of blazing from site to site to visit as many habitats as we can and find lots and lots of birds!

This event is a fundraiser for Point Blue, and as such, I ask that if you have the means please donate and support this amazing team of young birders (the longest running youth team that I have ever heard of!), and Point Blue. By donating this cause, you will be supporting climate research that is badly needed, and also supporting and encouraging young birders who represent a hope for the future of our planet that is also badly needed. You can donate by following this link and clicking the ‘donate’ button just to the right of the team photos.

My heart-felt thanks goes out to each person who contributes in support of this amazing cause.

#richstallcup #birdathon #birds #conservation

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Are humans still evolving? Have medical advances and the luxuries of modern life removed the pressures that natural selection might exert and so remove the driver for humans to change from generation to generation?

Sketch of median artery vessel which supplies blood to the human forearm and hand © Professor Maciej Henneberg
Sketch of the human forearm indicating the median artery (Image Credit: Professor Maciej Henneberg

Several examples can be pointed to which indicate that we humans are still evolving from increasing head size to the reduction in frequency of wisdom teeth. And a new example has just been discovered!

Researchers at Flinders University and the University of Adelaide (both in Adelaide, Australia) have discovered that some adult humans today have three arteries that bring blood to their forearm and hand, while the rest have only two. And the percentage of the population that has three is increasing. These results were published in the Journal of Anatomy in September 2020.

We all had three arteries in our forearms when in utero which are called the ulnar artery, the radial artery, and the median artery. But most adults only have two because the median artery (the one in the middle) generally disappears as a fetus develops. However, sometimes it never disappears, and adults will have a functioning median artery. This variation in development is where the researchers focused their attention.

Anatomists (people who study anatomy) have noted that the median artery disappears sometimes, but not always, for well over a hundred years. Some of these anatomists examined adults born in the 1880s and noted that about 10 percent of them still had their median artery and 90 percent has lost theirs. Researchers from those two universities in Australia mentioned above read these reports and wondered if those numbers had changed. They examined the forearms of adults born in the late 1900s and found that about 30 percent retained their median artery while the percent that lost their median artery was down to 70 percent.

Looking at those numbers, it might not seem very dramatic, but a 20 percent difference over just a few generations is pretty significant in evolutionary terms. If this rate of change continues, everyone born 80 years or more from now will have a median artery as adults. When most people have a median artery as adults, medical standards will need to change. At that point, having a median artery will be the normal condition, and no longer be considered a variant as it is today.

No one is sure why this trait is being favored. Having three arteries that feed the hand does allow for increased blood supply. While it might be tempting to try and explain this change as a reflection of how important hands are to our survival, that idea is not supported by any data. In fact, hands have been important for human survival since before we evolved into humans, so even the idea is a bit weak. Whatever pressures are causing natural selection to favor the retention of a median artery into adulthood is an interesting question that stands open.

This example of the median artery shows that humans are still evolving and that natural selection continues to influence our species even if we don’t understand why it may be occurring.

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A few years ago, I wrote a post called Lizards, Ticks, and Lyme. It explained how Western Fence Lizards (Sceloporus occidentalis) have a blood protein that kills the bacteria that causes Lyme Disease, and this is one of the major explanations of why Lyme Disease is so much less common in the Western USA.

Well, new research (see references at the end) has added a really intriguing facet to the Tick-Lizard-Lyme story. This new research focuses on the southeastern USA. The southeast is another area where Lyme Disease rates are very low. But why? The southeastern USA has populations of Black-legged Ticks (members of the genus: Ixodes), which are the ticks that can carry Lyme Disease. The region has the mammal species such as deer and mice that act as reservoirs for Lyme Disease. People in the southwest get bitten by ticks, just like other parts of the country. So why is Lye Disease so much more common in the northeastern USA than the southeastern?

Well, once again, it looks like we can thank lizards. Skinks are a group of smooth-scaled rather lovely looking lizards and they are one of the preferred hosts for ticks in the southeastern USA. In the northeastern USA mice are the much more common host to ticks. And this sets up a roadblock for Lyme Disease in the southeast because skinks have been shown to be really bad transmitters of Lyme Disease. Mice, on the other hand, have been shown to be very effective transmitters of Lyme Disease.

A Southeastern Five-lined Skink (Photo credit: Animal Spot)

It is not yet known if the stinks blood contains proteins that actually kill the Lyme Disease-causing bacteria, or it there is something else about skinks that reduces transmission rates, but this difference in host does help to explain why Lyme Disease rates are so much lower in the southeastern USA as compared to the northeastern USA.

So, fence lizards and skinks both contribute to reducing Lyme Disease in the areas where these lizards are found. Pretty fascinating stuff! I am very much looking forward to learning more about this subject as more research is done. Do other lizard species also reduce the occurrences of Lyme Disease? Does skink blood kill the bacteria that causes Lyme Disease? What is the blood protein that the fence lizards produce that kills the bacteria, and can it be synthesized? So many questions!

I hope you follow this story, and are as intrigued by it as I am. I will certainly write more as more is discovered.

Here are some sources for further reading: a Science News article, and an SF Gate article.

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