The Channel Islands have been battered by the ocean for a long time, eroding beaches, cutting into cliffs, and gradually wearing away countless cultural artifacts. While coastal erosion has primarily been a natural occurrence in the past, the situation is expected to worsen due to human-induced climate change and rising sea levels. In a desperate effort to preserve history, Erlandson and other historians are rushing to document and salvage artifacts that provide some of the earliest evidence of human maritime activity in the Americas. "We’re just hoping there’s something left," he expressed. 

​Read more about the loss of coastal archaeological artifiacts in the Channel Island here. 

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Humans have been generating and leaving behind trash for as long as they have walked the earth. These ancient lands, officially called middens are rich with archaeological data that informs on past people and ecologies. MinuteEarth offers a quick overview of middens in this ​​TikTok video. 

The Channel Islands are rich with coastal shell middens that offer valuable insights into ancient marine ecosystems and the impact of human activities on fisheries over millennia. Researchers studying the Channel Islands have focused on Middle Holocene shell middens, which are characterized by large and often intact shells of red abalone.  In the study "Fishing from Past to Present: Continuity and Resilience of Red Abalone Fisheries on the Channel Islands, California" looks at how people have managed red abalone over thousands of years. It shows that Indigenous communities in the Channel Islands had sustainable fishing practices that allowed them to use this resource without deplete it. These communities understood how to maintain a healthy balance in the ecosystem, ensuring there was enough red abalone for future generations.

In more recent times, however, modern commercial fishing has caused red abalone populations to decline dramatically, leading to strict regulations to try and save the species. The study emphasizes that we can learn a lot from the sustainable methods used by Indigenous communities. Combining their traditional knowledge with modern conservation efforts could help us better manage marine resources and protect them for the future.  (Braje et al. 2009)

The arrival of humans and the transported landscapes that they brought with them, altered the ecosystem throughout the Channel Islands. With the help of biologists, ecologists, and archaeologists, scientists have identified plant and animal species that have been introduced by humans as well as those that have gone extinct. While some of these transported landscapes were likely intentional and some may not have been, all have had an impact by altering the ecosystem of the Channel Islands.

In many parts of the world, a "natural state" is impossible to define. Archaeology contributes to these past baselines, but it is still up to conservationists today to choose what time period sets the tone for modern goals.  Islands are unique in two ways. On one hand, they are particularly susceptible to invasion of non-endemic plant and animal species. On the other hand, islands present a unique environment where the archaeological record can provide clues to help identify when plant or animal species arrived, whether or not that corresponds with the arrival of humans, and what impact they may have had on the ecosystem. In the Channel Islands. Because of this, islands are often studied to add to the body of knowledge about ecosystems and human impacts on them (Hofman and Rick, 2018).

Much debate surrounds if, when, or how non-endemic plant or animal species are handled, causing frequent clashes between modern residents and conservationists. For instance, over at least the last 13,000 years, there have been many groups that inhabited, settled, used, or explored the Channel islands. In all instances, there was the opportunity for non-endemic species to be introduced to the ecosystem.

Founded in 1972, the Catalina Island Conservancy is a non-profit public charity working to restore and protect Catalina Island for future generations to experience and enjoy. One of their objectives is restoration of the ecosystem to as natural state as possible.  These efforts have not been without pushback. The current debate centers on the mule deer that were brought to Catalina to hunt and promote tourism. With no natural predators on the island, the mule deer population is unsustainable and harmful. Their grazing damages native vegetation,  contributes to the loss of native plant species, allows for the spread of non-endemic grasses, and causes soil erosion. The Conservancy proposed culling 2000 deer but was met with opposition, some of which from families with generational ties to the island that claim a cultural tie to hunting. Previous to the mule deer, goats and pigs were successfully removed from the island as part of their ecological restoration projects. Citing the invasive grass species that acted as fuel in the deadly fires of Lahaina, the urgency of these projects is understandable (Invasive Species News). 

Beginning in the 1920's various mammals have been removed from the Channel Islands. For a list, more information about the science behind, and updates about Catalina island ecological restoration, visit the Catalina Island Conservancy's website. 

Up until about 11,000 years ago, four of the Channel Islands made up one large island, dubbed Santarosea, that was closer to the mainland that what is seen today. As sea levels rose, all but the highest elevations of Santarosea were submerged, leaving the four separate islands of San Miguel, Santa Cruz, Santa Rosa, and Anacapa (Muhs et al., 2015)​.

Initially discovered on the island of Santa Rosa, the pygmy mammoth is considered to have been endemic to the Channel Islands and remains have been found on all but one of the islands. Many of these remains can be seen at the Santa Barbara Museum of Natural History. 
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While the debate on the extinction of megafauna has not reached a conclusion. studies have indicated that the survivability of the Santrosea pygmy mammoths was compromised and therefore the species was suspectible to  extinction.  Research has shown that changes in climate and rising sea levels that shrunk the land area, resulting in reduced access to fresh water sources and altered vegetation that the pygmy mammoths relied upon (Semprebon et al., 2016).  But how about humans whose presence overlapped by at least 250 years with the pygmy mammoths (Agenbroad et al., 2005)?  We still do not know. As of today, no evidence has been found to directly show that humans hunted pygmy mammoths (Rick et al., 2012). Does that mean it didn't happen? Of course not and we may never know, especially since much of the coastal area has been reclaimed by the Pacific Ocean. 

It depends on who you are asking! As Professor Lisa Maher of UC Berkeley once said "humans have been creating and leaving behind a lot of garbage, for a very long time." With that garbage, ahem, artifacts, there is much to learn about humans and their impacts on their environments.