Help Rutgers University's Research on Leeches Attached to Catfish (Delaware River & Tribs, PA/NJ)

Hello, Blog Readers! 

Today I'm here to request your help in the name of science. If you fish for Channel Catfish (Ictalurus punctatus) or White Catfish (Ameiurus catus) in the Delaware River and its tributaries (i.e. Schuylkill River, mouth of Creeks, etc), here is a chance for you to be acknowledged in some scientific research papers (see rewards section below)! :) 

Summarizing, I received a very interesting e-mail from Rutgers University recently: scientists in the Biology department told me that they were conducting research on different local Species of "leech" that attach to fishes. They requested me to spread the word to the local fishing community, since they need live leech samples from the Delaware & its tributaries.

This is where you guys come in! Hah. If you ever catch a Catfish from the Delaware River or one of its estuaries, please check the fish for the presence of leeches! If you want to contribute to this research, please read the rest of this post (this event post will be on the right tab until the researchers no longer want samples). This post is divided in the following parts:

1. General information
2. How to identify the leeches. 
3. How to collect and preserve the samples. 
4. How to submit your samples.
5. Rewards and acknowledgments for participation 

--- 1. General Information ---

As mentioned previously, the collection of these leeches is for research purposes at the Biology department of the Rutgers University in Camden, NJ. In other words, your leech samples may be used for a PhD dissertation that will probably be in important scientific journals. As an example, here is a scientific paper on leeches that was published about two years ago in the "Journal of Morphology" (important people in the field reads this stuff, folks). The abstract is available for free in the website; however, the whole research paper can only be seen after purchase.

Therefore, as you guys saw, your "leech sample" will be used for very important purposes in the scientific community. For this reason, one needs to provide extremely accurate information when it comes to its collection. If you want to help by providing leeches for this research, the following pieces of information will be necessary:

(I) Your name: this will be used for acknowledgement purposes in the research paper, in case your sample is used.
(II) The location of the "catch:" since the leeches are attached to fishes, the site of the catch will be necessary. Recall: Delaware River & its tributaries only. A google maps/google earth pinpointed location is preferred and highly advised.
(III) The location where the leech was attached: from my personal experience, the leeches that I saw were attached mostly below the fishes' mouths or in their pectoral fins. Make sure to write down which portion of the fish the leeches were found and collected from.

These three pieces of information are fundamental and must be provided in case you decide to contribute for this research. As a scientist myself -- a physicist, I highly encourage all of you to participate, since you will be acknowledged if your samples are used (see section 5 for more details). :)

Additionally, samples are being accepted until the end of this fishing season (2015) -- unless noted otherwise.

--- 2. How to Identify the Leeches ---

I am well aware that it may be difficult for any of us to identify a leech. For your information, these leeches are not the traditional "dark" leeches that are used as bait. As a matter of fact, they are much smaller in sizes; usually concentrated below a fish's mouth or on its fins. Below is a photo for you folks to have an idea:

The left portion of this photo portrays a hand drawn diagram of a leech by Dr. Saglam. The right side portrays leeches attached to a Channel Catfish's pectoral fin (photo credit: Dave B.).

--- 3. How to Collect and Preserve the Samples ---

Since these leech samples will be used for scientific purposes, good collection and conservation of the same are essential. 

Anglers -- try to collect the leeches as smoothly as possible, preserving the sample as one. In other words, please avoid cutting/chopping them. The ideal situation would be to use a tool like a scissor or pliers to gently get the leech out of the fish, so that they are collected alive. 

For preservation, please place the live samples inside a small container with river water (if you are not sure about what "small" is, go with a pint). That should suffice. In case you are a scientist and you know what you are doing, you may also place the samples inside a small tube with 70% ethanol (I don't expect anyone to have conical centrifuge tubes and 70% ethanol at home, but you never know).

I am not sure if different Species of leech prefer different Species of fish. Thus, just in case, if you have different samples from different fish Species, please use one container for every fish. For example: if you found three leeches in a Channel Catfish and four leeches on a White Catfish, use two containers for it. Also, don't forget to label or mark the containers, so that I will know which belongs to which fish. 

Although this post only mentions leeches in Catfish, the ideal situation is for you to preserve any leech samples from any fish (just in case). In this scenario, please include the Species, besides the general needed information (section 1).

--- 4. How to Submit your Samples ---

Please submit your samples directly to me as soon as you can. Once I receive the samples, they will be submitted ASAP to Rutgers University. If you have any samples, please contact me on my Facebook Page (send a private message or post on the wall) or via e-mail at

I will let you know of my availability and we can schedule a place to meet. 

--- 5. Rewards and Acknowledgments for Participation ---

According to the Professor and Chair of the Biology Department at Rutgers University -- "All data will be presented in scientific journals with appropriate acknowledgement/authorship." In other words, your name will be there if your leech sample is used.

Additionally, albeit rare, sometimes a new/unsubscribed Species of leech may show up! You never know, right? If you provide your leech for this research and it turns out that your leech is a "new Species," you will have a high degree of input on naming this new Species. How cool would it be to name a new Species, eh? Hah.


Anyways...thank you very much for taking your time in reading this post, fellas. Once again -- I highly encourage all of you to participate in this research!!! Let's not forget that scientific discovery is a beautiful thing, and science is definitely the way to go in life. Here you have a rare chance of contributing to science using one of your passions in life: fishing. 

You bet that I will be doing some Catfish sessions in the Delaware River in the upcoming weeks! I want to supply my own samples as well. :) If you are willing to join me in those sessions, please contact me in any form of social media with the subject line "Fishing for Leeches" and I will keep you updated on the dates of those sessions! 

Best of luck to all of us,

Long Days and Pleasant Nights,


Leo S.


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