A big step to recover a tiny California fish

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Two biologists dressed in waders holding a seine net in the Topanga Lagoon. Photo credit: Vanessa Morales/USFWS.

Malibu, California— Found exclusively in California, the endangered tidewater goby (Eucyclogobius newberryi) is a tiny grey-brown fish rarely exceeding two inches in length and whose brief lifespan provides no shortage of challenges and threats to its survival. The fish has been listed as endangered under the Endangered Species Act since 1994, prompting scientists to work to save and recover the species. 

Close up of tidewater goby individual. Photo credit: Christine Fox/USFWS

After years of studies and planning, in late September 2022, biologists from federal and state wildlife agencies and universities worked together to catch and move 500 tidewater gobies from Topanga Lagoon (home to a thriving population) to Malibu Lagoon, where the population of tidewater gobies saw a great decline approximately two decades ago and has remained low ever since. Gobies from Topanga were put into coolers to be driven up the Pacific Coast Highway for release into Malibu Lagoon. This process is known as a translocation. 

The biologists are hopeful this translocation will result in an increase in the population of the tidewater gobies in Malibu Lagoon.  The augmentation of the endangered fish’s population would not have been possible without the support and permission of California Department of Parks and Recreation, since both Topanga and Malibu Lagoons are found on state park lands. 

“We are pleased to support the tidewater goby augmentation in Malibu Lagoon and look forward to continuing our partnerships that allow this great work to take place,” said Danielle LeFer, senior environmental scientist at California Department of Parks and Recreation, who participated in the translocation. 

Nurseries of the sea 

View of the Pacific Ocean and the Topanga Lagoon. Photo credit: Vanessa Morales/USFWS

Estuaries and lagoons are found where freshwater from creeks, rivers, and streams meet and mix with the salinity of the ocean. This delicate balance of salt and freshwater, or brackish water, provides a place for food, feeding, breeding and migration for a wide variety of fish, plants, and wildlife, including the tidewater goby.  

Not only do lagoons such as the Topanga and Malibu Lagoon nurture biodiversity and allow it to thrive, but they also help produce fish, store carbon dioxide, purify water, and protect shorelines from floods and erosion. Moreover, they are sometimes referred to as “nurseries of the sea” because they provide important breeding and feeding habitat for fisheries. Estuaries are also meaningful to the people who live in nearby communities because they provide places to gather, encourage recreation, and boost the local economy.  

Despite the numerous benefits brought by these bodies of water, more than 90% of the lagoons and estuaries once found along the California coast have been developed or destroyed.  Those remaining are often polluted, littered, dredged or filled. Biologists and water scientists are working hard to optimize and improve the few estuaries and coastal lagoons that are left.  

Species like the endangered tidewater goby depend on it.  

The problem 

Tidewater gobies being measured on a fish measuring board. Photo credit: Vanessa Morales/USFWS

Historically, tidewater gobies inhabited the brackish waters of lagoons along California’s coastline. However, in the 1980s, researchers observed the fish’s populations were vanishing from many of those bodies of water.  

Tidewater gobies face numerous threats to survival, primarily habitat loss, the introduction of non-native predators, and drought. The destruction of coastal habitat and the decline in goby populations led the species to be listed under the Endangered Species Act.  

In Malibu, native tidewater gobies disappeared from the Malibu Lagoon in the 1960s and re-established with fish from the Ventura River in the early 1990s. Tidewater gobies remained relatively abundant up to 2005, but their population declined for reasons that remain unknown.  

In 2012, California Department of Parks and Recreation led the Malibu Lagoon Restoration and Enhancement Project which provided many goals and benefits to Malibu Lagoon, such as improved water quality and improved native wetland and coastal habitat. Despite these efforts and improvements, the population of the tidewater goby has remained low in Malibu Lagoon. 

The plan 

The U.S. Fish and Wildlife Service completed the Tidewater Goby Recovery Plan in December 2005 with the assistance of species experts. One of the key recovery actions in the plan is to implement translocations where appropriate.  

Due to the unsuccessful attempt to recover the small fish after the Malibu Lagoon restoration, a local working group of agency staff and tidewater goby experts came together to address the problem. Meanwhile, surveys conducted annually in Topanga Lagoon for multiple years showed a robust population of gobies. The idea came forth that perhaps some Topanga fish could be moved to Malibu, but biologists would have to ensure gobies could survive and reproduce in the new location. In 2021 the California Department of Parks and Recreation funded a study to investigate water quality and suitable habitat.  

In May 2022, the results of the study confirmed Malibu Lagoon was a viable home for tidewater gobies.  
 
As a result of the study’s findings, the working group proposed to boost the tidewater goby population in Malibu Lagoon by translocating 300-500 individuals from Topanga Lagoon. Finally, the tidewater goby translocation to Malibu Lagoon would become a reality. 

The translocation 

Two biologists dressed in waders holding a seine net in the Topanga Lagoon trying to catch tidewater gobies. Photo credit: Vanessa Morales/USFWS

In late September 2022, biologists from the U.S. Fish and Wildlife Service, California Department of Parks and Recreation, the Resource Conservation District of the Santa Monica Mountains, and California State University Channel Islands met at Topanga Lagoon to initiate the translocation. Outfitted with waders, the biologists carefully entered Topanga Lagoon with a seine net to catch tidewater gobies.   

Seine net being pulled with dozens of tidewater gobies. Photo credit: Vanessa Morales/USFWS

Each time a net was pulled, hundreds of tidewater gobies were caught. Occasionally, a non-native or invasive species invasive species
An invasive species is any plant or animal that has spread or been introduced into a new area where they are, or could, cause harm to the environment, economy, or human, animal, or plant health. Their unwelcome presence can destroy ecosystems and cost millions of dollars.

Learn more about invasive species
, such as red swamp crayfish, would be captured and removed. 

Biologist observes tidewater gobies with a hand net. Photo credit: Vanessa Morales/USFWS

Next, the biologists examined the seines and selected the tidewater gobies that would be moved to their new home. Hand nets were used to transfer the tidewater gobies from the seine nets into buckets of clean water from Topanga Lagoon. The rest were immediately released back into the lagoon. 

After 500 individuals were collected, biologists placed them into coolers and loaded them carefully into a truck to make the journey north. 

Tidewater gobies in coolers ready for transport. Photo credit: Kirby Bartlett/USFWS

After arriving at the release location in Malibu, the gobies were given time to acclimate to the warmer waters of the Malibu Lagoon. Three sites were deemed suitable for tidewater goby release, based on available food sources and substrate. The coolers were carried or floated across the water so the fish could be released. The excitement was palpable among the biologists. 

“This translocation of tidewater gobies is really exciting because it is a bit of a homecoming," said Kirby Bartlett, a biologist at the U.S. Fish and Wildlife Service in Ventura. 

"The large tidewater goby population in Topanga Lagoon was recolonized by individuals initially from Malibu Lagoon in 2001. Tidewater gobies exist in a metapopulation network, which can be thought of as a network of individual populations that are occasionally linked through dispersal. Human impacts can inhibit how the metapopulations typically function, which can result in prolonged local extinction events like we saw in Malibu Lagoon. This translocation event will help strengthen the metapopulation network for tidewater gobies in Los Angeles and Ventura Counties," she continued. 

At last! The tidewater gobies had been released into their new home in Malibu Lagoon. The biologists who had been working for years on this release were elated to see this historical translocation and hopeful boost to the tidewater goby population. 

Two biologists float a cooler filled with tidewater gobies across Malibu Lagoon. Photo credit: Vanessa Morales/USFWS
Biologists carry a cooler filled with tidewater gobies to release them into Malibu Lagoon. Photo credit: Vanessa Morales/USFWS
Two biologists pour the contents of the coolers into Malibu Lagoon. Photo credit:Vanessa Morales/USFWS

The expected outcomes 

This translocation promotes recovery and provides an important buffer to reduce the likelihood of elimination of gobies from Malibu Lagoon.   

“This was a great team effort, and we look forward to checking on the gobies in the spring, hoping to see increased numbers,” said Eric Morrissette, senior biologist with the U.S. Fish and Wildlife Service in Ventura, California. 

All the biologists were excited to participate in the process and remain hopeful for this extraordinarily unique California fish species in Malibu. 

Biologists and scientists smile following a successful translocation effort at Malibu Lagoon. Photo credit: USFWS

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