Sawfish symposium in 2016

Hello all! At its 2015 annual meeting in Reno, Nevada (July 15-19, 2015), the American Elasmobranch Society announced that a symposium entitled “Biology and Ecology of Sawfishes” had been accepted for the 2016 annual meeting in New Orleans, Louisiana (July 6-10, 2016). 

The symposium is being organized by Dr. Dean Grubbs (Florida State University) and Dr. Gregg Poulakis (Florida Fish and Wildlife Conservation Commission) and anyone interested in presenting their data is encouraged to contact them (dgrubbs@bio.fsu.edu; gregg.poulakis@myfwc.com). Researchers from North America, Australia, and Africa are already planning to participate. The organizers are especially interested in bringing together international researchers and funding is being sought to aid international travel. Please spread the word and encourage anyone doing sawfish research of any kind to contact Dean and Gregg. 

We hope to see you in New Orleans! 

Mi experiencia en el curso de formación de pez sierra, Tumbes, Perú

Claudio Manrique

Traducido por Clara Vasquez & Ruth Leeney  

Durante la realización del curso de investigación y conservación de tiburones y rayas tuve la oportunidad de conocer –entre otros ponentes- a Ruth Leeney, especialista en el estudio del Pristis pristis o pez sierra, representante de Protect Africa’s Sawfishes (Proteja los Peces Sierra de África).

Primera vez que escuchaba sobre dicho pez, en realidad no lo había visto antes ni en fotos ni en dibujos. Tampoco en tiendas de artesanías donde suelen vender huesos de peces con picos alargados. Tampoco lo había visto como adorno en hoteles ni restaurantes.

'Rostra' (sierra) de pez sierra en el Museo de Historia Natural de Lima

De hecho -durante el transcurso de la primera semana del curso- surgió la incógnita de que podría haber algún ejemplar en algún restaurante de mi pueblo, Máncora. Llamé al dueño del restaurante El Espada donde cabía la posibilidad de encontrar algún ejemplar sea por el mismo nombre del restaurante o por referencia de algún conocedor de la zona pero tampoco nos dio razón sobre el pez sierra.

Sin embargo en las entrevistas de campo con los pescadores de la región Tumbes logramos recopilar testimonios de avistamientos de dicha especie, muy esporádicos a lo largo de las últimas cinco décadas y los más recientes durante el presente año y el año pasado en la misma época de verano austral lo cual motivo la investigación de la especie en la zona.

He aprendido a diferenciar al pez sierra del tiburón. He aprendido que existen cinco pez sierra. También he aprendido a trabajar en el campo de la investigación y búsqueda de información que ayuden a conocer más sobre el comportamiento del pez sierra mirando y siguiendo las indicaciones de Ruth y demás participantes del curso.

Un comportamiento del pez sierra que llamó mi atención fue su travesía por los estuarios posiblemente para su reproducción. A partir de ahí surgieron entretenidas conversaciones sobre la Amazonía. Ello me lleva a reflexionar que mientras más conocemos sobre una especie más conocemos del entorno donde vivimos y a la vez aprendemos a colaborar en su investigación y conservación.

Estoy muy agradecido de haber participado durante las dos semanas en las que se llevó a cabo el curso de paso aprovecho para agradecer a Planeta Océano por la beca otorgada, gracias! Por último animar a los principiantes a participar de iniciativas de conservación. En mi caso como habitante de la zona estaré atento a lo que suceda durante el fenómeno El niño que actualmente estamos experimentando.

 

Claudio (far left) and other course participants take a well-earned break after interviews with fishermen at Zorritos port.

My experience at the Sawfish training course, Tumbes, Peru

Claudio Manrique

Translated by Clara Vasquez & Ruth Leeney 

During the training course on the Research and Conservation of Sharks and Rays, I had the opportunity to meet, among other speakers, Ruth Leeney, a specialist in the study of Pristis pristis or sawfishes and representative of Protect Africa’s Sawfishes.

This was the first time I had heard about sawfishes. I had never seen them before, not in photos or drawings, in craft shops where often sell sawfish rostra (the 'saw' of the sawfish) or even in hotels or restaurants where the rostra are sometimes used as decoration. In fact, during the first week of the course, I wondered if there was perhaps a sawfish specimen at the restaurant in my hometown, called Máncora.  So I called the owner of the restaurant El Espada (‘The Sword’),  thinking the restaurant’s name might be significant, but unfortunately the owner had no information about sawfish. 

However, during the interviews we conducted with fishermen around Tumbes (northern Peru), we got testimonials of sightings and captures of sawfish in Peruvian waters, which have been very sporadic over the last five decades. The most recent sightings were during the austral summers of 2014 and this year.

Cristhian and Andres interviewing a fisherman on the beach

During the course, I learned to differentiate between sawfishes and saw sharks. I learned that there are five species of sawfish. Also I was able, by observing and following the advice of Ruth and other course participants, to perform interviews in the field and to collect information on the behaviour of sawfish. One behaviour of the sawfishes that caught my attention was their journey through estuaries, probably for reproduction. After that, we had some entertaining conversations about the Amazon. This led me to realise that the more we know about a species, the more we can know about the environment in which we live, and the more we can collaborate on researching and conserving these species.

I am grateful to have participated in this two-week course and want to thank Planeta Oceano for providing me with a scholarship to attend the course – thank you! And finally, I encourage beginners to participate in conservation initiatives. In my case, as an inhabitant of Peru’s north coast, I will now pay greater attention to what happens during the El Niño phenomenon we are currently experiencing.

Sawfish CSI: using DNA to unravel the past and protect the future

Dr Nicole Phillips and Kelcee Smith

The most distinct part of a sawfish is undeniably its saw. But this saw is also the Achilles heel of the sawfish, because it makes this iconic creature so susceptible to capture in fishing lines or nets and valued as trophies by recreational fishers. It is largely agreed on by experts that sawfishes have undergone substantial declines in range and abundance due to human activities, but the evidence for these declines is largely anecdotal. There is little information regarding past abundances of most sawfish populations, and it would seem impossible to go back in time to determine how large sawfish populations may have once been. It also seems impossible to know how ‘healthy’ these past populations were compared to the sawfish populations of today. But is it impossible? And why is it important to compare past and present populations of sawfishes?

 

A historic photo of a large number of sawfish captured by fishers.

Declines in abundance are typically also accompanied by declines in genetic diversity. Genetic diversity, in essence, is variations in DNA sequences, and when talking about genetic diversity in populations, this refers to animals in a population with different DNA sequences. Maintaining moderate to high levels of genetic diversity in a population is important because it allows a population to change and adapt to changes in the environment. Populations that have undergone drastic and sudden declines in abundance tend to have lower levels of genetic diversity, which may be less ‘fit’, more susceptible to disease, and less able to adapt in a changing environment.  If a population is very small, there may also be a risk of inbreeding, which is when close relatives mate and produce offspring that could have reduced fitness and possible birth defects, such as deformities.  

These peppered moths are the same species but differences in their DNA sequence has resulted in different physical appearances, making each more 'fit' or better suited for different environments. Genetic differences within a population may be relatively small and are not always observable.

It is important to have an understanding of the levels of genetic diversity in present day sawfish populations so we can identify and protect populations that are genetically less diverse. It is also important to understand how the levels of genetic diversity in present sawfish populations compare to those in the past to determine if these levels have declined over time. We are fortunate to have old sawfish saws available in museums, and sometimes in private collections, as these saws can be used as a resource for studying past sawfish populations. Some of these saws date back to the 1800’s and are the only remaining evidence that sawfish once existed in certain locations around the world. These old saws not only provide insights into the levels of genetic diversity of past populations, but the DNA can even be used to estimate past population sizes, which can be compared to current day sawfish population sizes to look for evidence of declines in abundance.

A sawfish saw that was kept as a fishing trophy.

Such research is not without its own set of challenges. Finding adequate numbers of samples is the first major hurdle; working closely with many researchers and museums is key. Once the samples are collected, the next set of challenges researchers are faced with is generating usable data from old saws that were not stored for DNA research. While at Murdoch University in Western Australia, and with some help from an honors research student, Dr. Nicole Phillips spent a number of years working out the best type of tissue to sample on a saw. This work included testing various ways to extract the DNA and testing different genes as well as different sizes of genes, since the DNA is often broken down into many small fragments. A lot of time was spent during this developmental phase so other researchers could take samples from rare saws efficiently and effectively. Nicole’s research into levels of genetic diversity of past sawfish populations has focused on the largetooth sawfish (Pristis pristis) and the green sawfish (Pristis zijsron) and she will be continuing this research at the University of Southern Mississippi later this year with a number of other researchers. This research will compare levels of diversity in past populations of the largetooth and green sawfishes to those of current populations to determine if there has been substantial declines in diversity (and abundance) and what may have been lost in terms of genetic diversity from regionally extinct populations around the world. 

Dr. Phillips taking tissue samples from an old sawfish saw in northern Australia.

Dr. Sabrina Taylor and Kelcee Smith at Louisiana State University are currently tackling the question of whether there has been a loss of genetic diversity, and by extension, effective population size in the smalltooth sawfish (Pristis pectinata) in Florida. They are collaborating with scientists from the National Marine Fisheries Service (NMFS) and the Field Museum of Natural History. The smalltooth sawfish is currently the only species of sawfish found in U.S. waters and is listed as Endangered (since 2003) under the Endangered Species Act. If this research finds that there has been a substantial loss in genetic diversity over time, then management efforts should focus on maintaining and increasing abundances of these sawfish, particularly in a variety of locations and habitats across their distribution in Florida.

These research projects may demonstrate that genetic diversity in sawfish populations have declined, indicating that there have been substantial decreases in abundance of sawfishes. Alternatively, we may find that the current levels of diversity have been maintained throughout the 1900’s despite the anecdotal evidence of large declines during this time period. Regardless, the opportunity to use sawfish saws in genetic analyses provides us with a glimpse into the past and provides information vital to the conservation and recovery of these sawfish species.