Human impact on our aquatic environments is something that each of us has the ability to minimize. Many people are unaware of the impact that they create each time the step foot into the water. Simply steeping on the sea floor has the ability to kill creature that live in the mud or sand. Education of human impact is something that is often rushed through during diver training courses. This topic can have lasting effects in preserving our underwater playgrounds and many marine species homes.

Dead Sea Lion

Photo by Phil Garner: If not removed, a gill net will continue to kill marine life for decades to come. Just one of many examples of the selfish, destructive impact that humans create. Groups like the Ocean Defenders Organization are helping by removing abandoned nets in the Southern California area.

http://www.leginfo.ca.gov/pub/09-10/bill/sen/sb_0001-0050/sb_21_bill_20100610_amended_asm_v96.html

Most of us have experienced the joy of diving in a lush aquatic environment. Can you imagine what it would be like after a few years of repeated abuse. Unfortunately, I have seen it happen numerous times. How many times have you heard a diver say a dive location is dead, or fished out ? And, with their spear guns in hand, they move on to another location. The greed and "machismo" that this sport attracts is unfathomable. If we can take some of the "SPORT" out of diving I think we would all be much better off. I am not completely against fishing but I think that some ethics need to precede. Fish should not become simple targets for a spear fisherman's practice shot. A marine reef can undergo devastating changes just by simply shooting one of its residents.

UB88 Submarine conning tower

The need for preservation is not something that diver alone need. For an ecosystem to thrive, all species, from the smallest to the largest, exist in a symbiotic relationship that maintains an equal balance. From the phytoplankton to the large predators, these species are significant in creating a balanced food chain for one another . Artificial marine habitats, like this TBM Avenger airplane wreck, create a new residence for a ecosystem to thrive. It's a given that this type of artificial reef will naturally deteriorate over time. Human impact will only expedite this process if not carefully managed. Wreck salvage and poor anchoring techniques are a couple of the ways that the premature breakdown of these habitats can occur.

TBM avenger Navy Airplane
Tying into a wrecks is a procedure in which a dive vessels anchor chain is shackled to the wrecks structural steel or a grappling hook snags the wreck and rope is used to tie it in place. This technique is popular on the east coast of the United States. More often than not, this unnecessary technique will deteriorate the integrity of a wreck as the dive vessel repeatably yanks on the chain while it rock and rolls on the surface above. In places like Southern California, where currents are generally minimal, this technique is completely inappropriate and only adds to the destruction of a marine habitats and our underwater playground.
Clevis
A remedy for this is to learn how to dive with a live boat when currents are present. A shot line is dropped up current of the wreckage. Divers time their entry. They enter the water and drift into this ascent/descent line performing an S-Drill and Bubbles check on their way down. Upon their ascent, they can choose to use this line if no currents are present. Otherwise they will deploy an inflatable surface marker buoy and drift during the decompression stage of the dive. The dive vessel will follow the buoy while the divers below decompress comfortably without the need to fight the current. No JON line is necessary. East Coast wreck diver may argue the point that they have strong currents, but I would like to remind them how the USS Monitor is dove. And a little advice, "never put more divers in the water than the surface support can handle".

surface marker bouy
It often comes as a surprise to divers when they find out how easy it is to damage a ecosystem. Cenote's, spring's and ponds are small bodies of water compared to large lakes and oceans. A little encroachment can go a long ways. Clothing detergent, hand soap, sunscreen, lotions and bug repellants can be toxic and capable of killing marine plants and animals. This impact is easily seen in the Yucatan Cenotes, where water flow is at a minimum. Damage has also been seen within the caves from the rapid development of resorts in the area, Foreign alginates have begun to attach to the insides of some of these aquifer's as waste water has been injected into the ground. A good reason to drink bottled water in Mexico.

John in Cenote Minotauromoskito

Products such as bug repellents, soaps and sunscreens can have deadly effects on the aquatic fauna. To limit any impact, divers may want to take a little more time in the shower by thoroughly rinsing soap off their bodies before heading out for a cenote or cave dive. Instead of sun screen, wear a shirt and hat. Rather than using DEET based bug repellents, dress with long sleeves and pants, keep the air conditioner on and the windows up. Or choose a repellent that is more environment friendly like those made with oils from the Lemon Eucalyptus. And have a strategy that allows you to suit up quickly before the critters eat you.

insect_repellentsbaby_sunscreen

Below is an interesting article I found about the "potential" risks of using sunscreen

Sunscreens Can Damage Skin
sunscreens-can-damage-7710
UV filters generate reactive oxygen species in skin
Credit: K. Hanson, UC Riverside
Are sunscreens always beneficial, or can they be detrimental to users? A research team led by UC Riverside chemists reports that unless people out in the sun apply sunscreen often, the sunscreen itself can become harmful to the skin.

When skin is exposed to sunlight, ultraviolet radiation (UV) is absorbed by skin molecules that then can generate harmful compounds, called reactive oxygen species or ROS, which are highly reactive molecules that can cause "oxidative damage." For example, ROS can react with cellular components like cell walls, lipid membranes, mitochondria and DNA, leading to skin damage and increasing the visible signs of aging.

When sunscreen is applied on the skin, however, special molecules - called UV filters - contained in the sunscreen, cut down the amount of UV radiation that can penetrate the skin. Over time, though, these filters penetrate into the skin below the surface of the epidermis, the outermost layer of skin, leaving the body vulnerable to UV radiation.

Led by Kerry M. Hanson, a senior research scientist in the Department of Chemistry at UCR, the scientists report that three UV filters (octylmethoxycinnamate, benzophenone-3 and octocrylene), which are approved by the Food and Drug Administration and widely used in sunscreens, generate ROS in skin themselves when exposed to ultraviolet radiation, thus augmenting the ROS that is naturally produced. The scientists note that the additional ROS are generated only when the UV filters have penetrated into the skin and, at the same time, sunscreen has not been reapplied to prevent ultraviolet radiation from reaching these filters.........

skincancer

A environmentally safer way to protect yourself from the sun.
mexican sunscreen

Poor diving technique is another cause of human impact while diving. In an overhead environment, bubbles alone can break down materials from the ceiling. It's best to stay close to the main guide line where this breakdown has already occurred, preserving the rest. Poor finning techniques can stir up silt and kick objects loose. Attention should be paid so the scuba equipment of a divers back isn't rammed into anything hanging above them. Proper training and good ethic can lessen these sorts of effects.

example of good diving techniqueAktun Ha cave damage
Left: Example of good diving techniques where divers stay close to the main guide line. Proper technique requires good training, conscientious practice and ethics. These cave decoration are pieces of art which took tens of thousands of years to create. They can be destroyed in a fin kick. In order for divers to maintain the permission that we have been granted to explore these cave, preservation should be of high priority. Right: Aktun Ha cave shows an example of repeated impacts on the calcite formations.


Disclaimer:
This site is NOT intended to teach anyone how they should dive. It is simply reflecting on what I have done and continue to do and is my opinion only. Proper dive training should be gained before attempting anything involving the use of a Self Contained Underwater Breathing Apparatus (SCUBA).