Reef and Fishery Assessment of Navassa Island National Wildlife Refuge

On April 23, 2009 scientists from the NOAA's Southeast Fisheries Science Center in Miami Florida (SEFSC) departed from San Juan, Puerto Rico aboard the NOAA Ship Nancy Foster. Their destination: the Navassa National Wildlife Refuge. Along with the NOAA scientists are researchers from the University of Miami's Rosenstiel School of Marine and Atmospheric Science (UM/RSMAS), the US Fish and Wildlife Service (FWS), and the Director of the Fondation pour la Protection de la Biodiversité Marine (FoProBiM), an NGO based in Haiti.
This work is funded by the NOAA Coral Reef Conservation Program.

Wednesday, May 6, 2009

The way back home

As we have had a day to contemplate the outcomes of the cruise, I think everyone is fairly pleased. Completed reef assessment objectives included reef fish visual census at 69 stratified random sites with photo-quadrats at 36 of these sites to characterize benthic cover. Among these random sites, only 7 were observed to host ESA listed staghorn coral (small, isolated colonies) while the invasive Pacific red lionfish were observed at four. Of the almost 29000 individual fish recorded in visual censuses, only 15 individuals were of large grouper species (Nassau, yellowmouth, and hind). Permanently tagged ESA listed elkhorn coral colonies were re-surveyed and all colonies along the southwest coast were mapped. This population remains in excellent condition. For the first time, the project (in collaboration with FoProBIM) was able to obtain pilot catch data (two boat-days worth were identified and measured) from the Haitian fishers who frequent Navassa waters. Reef temperature data was also retrieved from two logging sensors deployed in 2006. We look forward to compiling our results more completely and providing them to natural resource managers at the Caribbean Islands National Wildlife Refuge and the Caribbean Fishery Management Council. We never know when or if our next opportunity might be to visit Navassa, so while we are all happy to be headed home, we are all mindful of what ongoing changes may occur under the crystal clear waters of Navassa.

--Margaret Miller

Birds of Navassa, April 2009

red-footed booby - 285 (a.m. count)
brown booby – 45
white-tailed tropicbird - 8
magnificent frigatebird - 12
cave swallow - 6
snowy egret - 2
peregrine falcon - 3
gray kingbird - 1
great blue heron - 1
cattle egret - 1
broad-winged hawk - 3

The booby species partition habitat. The red-footed boobies nest and roost in the shrubby trees along the slope and top of the island, while the brown boobies roost along the craggy rock face and cliffs at the lower edge of the island. The red-footed boobies appear to be more numerous, at least in April. And they have many color morphs, from mostly white with black wings to overall brown. They leave the island just after sunrise in search of food offshore, and they return just before dusk. They have to run the gauntlet to get back to roost, as the frigatebirds circle and hover, ready to poach a meal from the returning boobies. The brown boobies fly under the radar, so to speak, low to the water which makes it more challenging for the frigatebirds. The red-footed boobies fly high and have frequent in-flight acrobatic tussles with frigatebirds.

The falcons flew over the ship Friday afternoon and circled overhead for hours. We never did see them return to land. A lone gray kingbird landed on the ship and the CO took some nice close up photos. The cattle egret landed on the crane boom, and the CO photographed him too. The two snowy egrets flew past together, winging along the island shoreline but not landing.

There were no birds along the north side of the island when we pulled anchor Monday evening at 6:00 pm, very severe landscape with few live shrubs. We did see 3 goats, though, along the top of the steep slope on the north side.

-Photo by Abel Valdivia(boobie above diver)
-Photo by Ralph Rogers(kingbird)
Contributors: Patricia Morrison, Mike Judge, Ralph Rogers

Tuesday, May 5, 2009

Elkhorn Coral Mapping

During this visit I attempted to repeat my 2006 circum-island snorkel to map the shallow Elkhorn coral population. I am really disappointed that I was only able to survey the west side of the island due to rough conditions on the north and east sides. Since the coral grows on the wall I have to snorkel very close to the rocks and mark each colony with a waypoint using a hand held GPS in a waterproof case. The photo shows the view from a snorkel perspective.
However, I was able to cover nearly 2 miles of coastline and count approximately 1000 colonies of Elkhorn coral! Each yellow dot on the map is a waypoint marking the location of a single colony. They appeared to be healthy and thriving as I remembered from our last visit 2 1/2 years ago when I counted approximately 900 colonies in this same stretch of coastline. It is very difficult to count colonies so finding 100 more on this visit does not necessarily mean there is more coral. Elkhorn coral colonies can split into smaller sections as it dies back so that one large colony may appear to be 2 or 3 smaller colonies on a subsequent survey which can really confuse things for us coral counting types! Regardless, this survey shows that there has not been a major loss in elkhorn coral aalong the west side of Navassa in the past 2 1/2 years.

Monday, May 4, 2009

Scene of change

Yesterday, on our last afternoon at Navassa, I spent one dive revisiting a site along the west wall base where we marked permanent 1m2 plots in 2002. I knew that there had been a lot of change in this reef from hurricanes and coral disease in 2004 and probably from coral bleaching in 2006. I was somewhat shocked when I actually got the pictures back last night and compared them with the earlier versions of themselves. I am showing just one example here to give you the idea. This 1m2 area of reef had been home to a decent sprig of staghorn coral, as well as nine juvenile coral colonies of various species in November 2002 (left image). Today, (right image) a single live coral colony is visible in the quadrat (though it appears to have grown a bit). This colony is outlined in both photos to help convince you that it is the same area. Otherwise, it is pretty unrecognizable, with a brown leafy-looking seaweed covering most of the area. This alga, Lobophora variegata, may be somewhat seasonal, but it covers the majority of Navassa reef surfaces at the moment. It will take some time to analyze all the benthic cover data from the transects and photo-quadrats we took at the sites of the fish surveys, but my impression is that more live coral cover remains on the deep patch reefs along the shelf, than in the nearshore habitats around the wall base where these permanent quadrats are located.

Photo by Margaret Miller
--Maraget Miller

The Last Stand?

As I mentioned in an earlier post, all divers have been keeping a sharp lookout for Staghorn coral, a threatened coral that has become tragically rare on Navassa's reefs. One small colony was spotted early on by Jack during his fish count. Staghorn coral can grow in shallow habitats along with its sibling Elkhorn coral but we have never seen it in the shallower part, only on the deeper (80-100ft deep) patch reefs. Our group has done more than 160 dives on this trip and we have found 4 small sprigs of staghorn coral. I joined the hunt focused only on finding this coral rather than other tasks so I am able to cover a relatively large portion of the patch reef when I tag along and that is how I found this small 5ft x 2ft stand of staghorn coral. Unfortunately it was mostly dead due to the three spot damselfish that set up his algae farm on the branches (click to bigify and you may see him in the dead part of the colony). This staghorn sighting was on a deep patch reef built almost entirely of HUGE mounds of now dead finger coral (the purple nubby stuff in the left side background is live finger coral). My guess is that most of it has died within the last 10 years so it was a very sad sight!
Today is our last day of diving and I am going to do 2 deep dives in the morning and will hopefully find more. Sadly this small (ok, very small) 'stand' of staghorn coral may be the last! So sad.... Dana

Sunday, May 3, 2009

Our last night with Navassa’s Boobies & Frigatebirds

It’s Sunday one week after we arrived at Navassa Island. We are all sad because tomorrow will be the last day of dive operations but at the same time we are happy to begin our steam home. The birders on the ship are particularly sad to be saying goodbye to our now nightly ritual of watching the boobies return home trying to avoid the ever present harassment from the Frigatebirds as they try to steal a meal from a tired or inexperienced Boobie. The swooping, diving, and aerial combat taking place between these two heavyweights of flight is truly a great sight to see. The sun setting over the ocean complete with green flash and brilliant orange hues only adds to the great evenings we have enjoyed on the Nancy Foster. I wish sunsets could last forever but soon after the sky gets to dark to see we return to our data entry and other nightly responsibility.

Something is Fishy

Our activities with the fishers began this morning. The boat which arrived last night pulled alongside the NF and was handed two coolers to collect the contents of two traps. They were also given a GPS unit to track their whereabouts as they checked traps around the island. When the coolers were returned to us an hour later the fishers were then given two more cooler to fill with the contents of their traps for the remainder of the afternoon. When these coolers arrived the fishers waited patiently as we measured the length and took the weight of their catch. We will be continuing similar activities tomorrow.

-Jean Wiener

Saturday, May 2, 2009


Each afternoon between 1630-1645 the dive teams return for the evening. The small boats come alongside the Nancy Foster and the scientific field parties climb up the ladder onto the ship. After everyone is safely aboard, the boatswains (pronounced bosuns, the persons in charge of a boat- the literal translation meaning ‘boat servant’), lower the crane cable to the coxswains to hoist the small boats aboard the ship (please see morning operations blog for more detail). After the chief boatswain Greg Walker gives the all clear, the scientists unload their gear and rinse it with fresh water. The coxswains rinse, refuel, make any mechanical adjustments, and prepare the boats for the following day's operations. Jack Javech and Steve Matthews fill tanks. For our Navassa dive operations we are breathing an enriched oxygen gas mixture called Nitrox. Normal air is approximately 21% oxygen, our Nitrox mixture is approximately 36% oxygen. Since the divers are making repetitive dives to between 90 and 100 feet, breathing Nitrox instead of air increases the amount of time we can spend at depth and also decreases the amount of time we have to spend at the surface between dives. We are able to do our jobs much more safely and efficiently. After showers and dinner we assemble in one of the ships labs for an evening debriefings by chief scientist Dr. Margaret Miller and diving supervisor Dave McClellan. During this meeting Dave conducts a post-dive safety check, Margaret discusses the days mission and plans for the next day are made. The meeting also gives us an opportunity to share stories and check out the day's photos.


Haitian fishers arrive!

Late this afternoon three fishers arrived from Anse d’Hainault, Haiti. They explained the difficulty of the crossing by sail and stated that one of their friends would be arriving tomorrow. Tomorrow we will provide them with coolers and a GPS tracker in order to begin to monitor their activities. They intend to raise some of the traps which have been observed around the island; from this we hope to gather information about catch per unit effort.
Photo by Abel Valdivia
Jean Wiener

Best laid plans….

Diving operations have proceeded without incident, except sea lice have plagued some our divers, Benadryl lotion being applied liberally and antihistamines swallowed. To complete the mission so far, 66 dive trips with154 total dives have been completed. Cumulative dives total 96.4 hours (4.8 days) with divers descending 11,961 feet (2.27 miles) underwater.
Since we needed counts on the north side, we decided to send 3 small boats with fish counters. After launching at 0800, the Foster pulled anchor and rounded the point so we could be in radio contact. As loose items began hitting the floor, I looked out the window and saw waves breaking, realizing that conditions were marginal. The ship began pitching and rolling, queasiness set in, and afternoon plans changed immediately. Back to the west side for sure! Watching the small boats bounce around and NF5 asking for an alternate site away from the shore, made me realize my name would be a cussword for awhile. Maybe locking the door to my cabin would be appropriate!
Photo by Abel Valdivia
Dave Mc

RVC fish count update

After 5 days of diving, 34 RVC sites (72 fish counts) have been completed. Since the weather has abated somewhat, we have been able to sample the north sites, where the habitat is different from the west side, so more species are being seen. Over 15,000 individual fishes from 102 species, with another two species new to Navassa, have been seen. The sailor’s choice grunt (Haemulon parra) and the lionfish (see lionfish blogs) have now been documented. Planktivores are again the most common trophic level; the most common species have been the creole wrasse and blue chromis, comprising 41% of the total number. Of the carnivores, the coney (114) and graysby (42), are still the most common groupers, but the Nassau (6), rock hind (1), yellowmouth (3) and scamp (4) groupers are also being recorded. The snapper complex is represented by the dog (5), schoolmaster (41) and yellowtail (1). An almaco jack and a few bar jacks have been observed, and the black durgon (584) is the most common triggerfish. Grunt species are extremely rare, only 6 French and 1 sailor’s choice being seen. Even though our RVC team has not seen a hogfish, the coral group has observed (see picture) a large individual. Long-spine diadema are being seen in almost 20% of our samples, greater numbers (30) than during past cruises. Very few queen conch and spiny lobsters are being recorded.
Photo by Margaret Miller
Dave Mc, Jack, Natalia, Joe, Dave G, and Mike

Our new Arrival... Navassito!

Its a boy... girl.... both actually! Elkhorn coral is one of many hermaphroditic corals so it is both male and female at the same time. Every August after the full moon adult colonies release gametes that float to the surface and fertilize to form a coral larva (planula) that will be carried by the currents for a week before it lands on the reef and turns into a baby coral. If they beat the odds and make it to the right place on the reef they still have to survive many potentially fatal assaults from algae, sand, urchins or other predators to make it to a size that is even visible to the naked eye. So, when this happens there is cause for celebration, especially for the threatened Elkhorn coral!

While surveying our Elkhorn coral study plots on the Northwest Point of the island we found a new baby Elkhorn coral! It was about the size of a US silver dollar and was not there (at least not visible) when we last surveyed in 2006 and it is bigger than we would expect for a 9 month old born in August 2008 so it is at least a year and 9 months. If it were born in August 2006 we would not have been able to see it due to its small size during our November 2006 visit so it is probably at most 2 years and 9 months old. We were very excited and decided to name it Navassito. Welcome to the world Navassito!

Friday, May 1, 2009


After the boats are put in the water and the dive teams are loaded we head out to our survey locations (please see RVC methodology blog for survey design information). The divers put on wetsuits for warmth and protection from stinging sea creatures like fire coral, jellyfish, and sea lice. Divers wear standard dive equipment like a scuba tank for an air supply, BCD, and regulators which attach to the tank and permit the diver to breathe underwater. The science divers carry clipboards with waterproof paper, measuring sticks and cameras down with them to document what they see. The diver teams also use a dive flag/GPS system which remains on the surface and is attached to a reel of line which the divers carry down with them. This serves a dual purpose by marking the exact location of the area sampled and providing a visual marker on the surface as to where the divers are. The divers (divers always go down as buddy pairs), do a back roll into the sea and descend to the planned working depth. For this mission it is very important that the divers do not go below 100 feet deep. When sampling is completed, the divers return to the surface and are retrieved by the coxswain of the small boat who remains close and maintains a watchful eye on the divers below. On the surface, the coxswains record the time the divers enter and exit the water which they then radio back to the diving supervisor Dave McClellan on board the Nancy Foster.


Catch of the day

The Indo-Pacific red lionfish (Pteroides volitans) is one of the most attractive as well as dangerous reef fish from the family Scorpaenidae. This group includes hundreds of members and some of the world's most poisonous fish species. Sharp spines coated with venomous mucous characterize the family. Generally the spines of the dorsal, pelvic and anal fins have venom glands at their bases. The pectoral fins are supported by long rays and do not bear spines.

Interestingly, a few of the lionfish's cousins are native and commonly found on the coral reefs of the Caribbean, Florida, Bahamas and Bermudas such as the spotted scorpion fish (Scorpaena plumieri). While scorpion fish are native of the region, the red lionfish was introduced to Florida in the early 1990s. During the last ten years the species has expanded slowly south across the region. Sightings have been documented from Bermuda, North Carolina, west coast of Florida, Bahamas, Puerto Rico and Labadee in the north coast of Haiti. Two days ago we documented the first three individuals in Navassa Island.

The red lionfish is not a native species of the West Indies region and the ecological and economical implications of its introduction are still unclear. The species is a top voracious predator, ambushing and sucking their prey like groupers and toadfish do. With very few natural predators, their diet consists of crustaceans, small fish, and even juveniles of their own species. The long pectoral fins and the striped colorations create a disruptive coloration that with their sneaky behavior is a fatal combination for their prey.

This invasive species evolved in a different natural environment and the consequences of their predatory behavior might be detrimental for the native species of the region. Limiting the spread of the red lion fish in the region is being attempted in most regions to avoid potential ecological shifts in the natural ecosystem. Yesterday, Mandy and I when for a lionfish hunt session in the afternoon, put our red protective equipment on, dove down 90 feet, found this misplaced creature underneath a fish trap, took a net, got the lionfish in the net, closed the net, snapped some shots and went up. Unfortunately, that was the end of this lionfish's life.

The hunt for the lionfish is now on. By the way, if stung by a lionfish, a common treatment is to soak the affected area in hot water. Although they spines are not deadly they might be very painful and could cause anaphylaxis reactions in susceptible individuals.
1st photo by Margaret Miller
2nd photo by Abel Valdivia

__Abel Valdivia

Domestic Animals Out of Place

As an artifact of intermittent human occupation dating back to the late 1800s, domestic animals (dogs, cats, and goats) have occupied the remote island of Navassa. Some of those animals persist today. During our research mission thus far, we observed 3 feral cats roaming the old stairways near Lulu Bay. These cats are NOT wildlife, and they can have devastating impacts on native species. On an island with no native mammalian predators, these cats are efficient hunters of birds, bird eggs, and probably lizards. While there are many places in society that are appropriate for cats, national wildlife refuges, such as Navassa, are not among them.
Photo by Abel Valdivia
- Patricia Morrison

First Turtle Sighting!

Yesterday I started our Elkhorn snorkel mapping and happened on ALOT of healthy Elkhorn Coral! I will blog about that more later, but the more exciting thing is that I saw the first turtle that has been seen on this trip. It was a small Hawksbill turtle swimming along the wall. He was rather startled and I was caught off guard since I was in Elkhorn search mode, but I was able to snap a quick picture of him (Click to see it better). We should have seen more by now so hopefully this is only the first of many turtle observations. I see them pretty frequently in Florida, but no matter how often I see them I get excited! Dana

Thursday, April 30, 2009

Spectacular sponges spawn sperm

This morning at northwest point we observed a group of Giant Barrel Sponges, Xestospongia muta, releasing sperm. The spawning occurred in all individuals in the area at depths of 10 to 15 meters and occurred from 9.30 to 10.30 in the morning, but we observed only males. These sponges are common on Caribbean coral reefs and can reach sizes of up to 6 feet. However, little is known about reproduction in the species. In 2004, Williams et al sighted a spawning event in Belize, which took place on March 30th in the early morning hours. In previous years, the Leathery Barrel Sponge, Geodia neptuni, has also been observed spawning at Navassa during the fall season.

Hump Day – A Historic Lionfish Day

I started writing my blog this morning after my first trip out in the small boat. Usually we do two dives each trip. I wasn’t sure what to write about, so I decided that since today marks the middle of our expedition, hump day (it is our 8th day in Navassa and the 4th day diving), I was going to write about my impressions of the first half of the trip: the weather has improved, operations have been running smoothly, and even though we are still looking forward to interviewing some fishers, we have been diving and conducting coral reef fish and benthic assessment successfully. Also I wanted to mention that I am part of a RAD (Rapid Assessment Dive) team, where two divers do reef fish visual census (RVC) and one diver does benthic assessment. Normally we go out twice a day, once in the morning and once in the afternoon, and we do two dives per trip.

While I was trying to get inspired to write my first Navassa blog, Dave Mac called me to go on my second trip out, which usually happens later in the day but today there was one boat that came in earlier. We got ready pretty fast and by 1250 Jack, Steve and myself together with our coxswain Trey were on our way to the dive site. We went in the water at 1307 and dove down to about 94ft to patchy hard bottom in sand habitat. Jack tied the reel and I positioned myself to start my RVC count. A few minutes into my count, while rotating and recording all species of fish observed I looked down, and to my surprise inside of a barrel sponge I saw two lionfish! Lionfish are invasive and spreading rapidly throughout the Caribbean. Both fish were predominantly black and white, characteristic of the “black” lionfish. The largest individual was 25cm (both photos) and the smallest 18cm long (fork length). When I approach them the larger fish came out displaying its beautiful patterns and ornate fins, but after a minute or so it went back into the sponge. The smaller fish stayed in the sponge the entire time. I took photos and video of both fish. Upon arrival to the ship, we found out that about 20 minutes before my observation, Margaret had also seen one smaller lionfish while diving one of the fish traps. So, today is not only hump day for our expedition, but is a historic day. Today officially marks the first time a lionfish has been observed and recorded in the RVC database, and also around Navassa Island!

Natalia (photos)


While we were doing our second count of the afternoon a large dog snapper Lutjanis jocu swam into my sampling area. It is rare to see large fish around Navassa, and we are always on the lookout. I snapped a couple of photos from far away just to prove I saw it and continued working. After finishing my count I headed toward my buddy Mike Judge who was just finishing his count nearby. We were both surprised to see the same snapper heading toward us and we immediately began snapping pictures. It was obvious there was something wrong with this fish, and as he got closer- right up to us- we could see he was disoriented and had scrapes and cuts all over him and his fins were also frayed. (We later speculated that he might have been in a fish trap and somehow escaped). In my experience, it is very rare to be able to approach a dog snapper so close. We took a bunch of photos and one of Mike's photos, with me in the background, is included here.


Submerged walls

The topography of Navassa Island is unique. It was once believed to be a small uplifted atoll with a volcanic core and surrounded by a fringing reef. However, the island is only a small portion of the Navassa Ridge above sea level. Located on the Gonave tectonic microplate, and caught in the great strike-slip faults between the Caribbean and North American plates the region is still seismically active today. Due to uplifting and folding processes during the Miocene, Navassa is characterized by sharp cliffs creating submerged walls. The submerged wall, heavily eroded at the surface by the wave action, runs vertically down to 50 or 80 feet deep. This particularity creates a habitat similar to those found in the platform drop off of some islands in the Caribbean. Covered majorly by sponges, seafans, tunicates, calcareous algae and scleractinian corals, the wall offers one of the best diving sites around the island. There are few species of sponges and gorgonians solely found in this kind of environment such as the Devil’s Sea Whip (Ellisella barbadensis) characterized for a single long axis full of polyps. The wall ends in the second or third underwater terrace around the island. But about terraces will be the next blog.
Photo by Abel Valdivia
Abel Valdivia

Wednesday, April 29, 2009

See how they grow

On my last visit to Navassa in 2006 we tagged about 70 Elkhorn coral colonies in study plots so that we could monitor changes in the population on subsequent visits and compare them to those we see among our other study plots in Florida, Puerto Rico, Curacao, Virgin Gorda and the Lesser Antilles.
So far I have visited the plots in Lulu Bay on the south side of the island and am happy to report all tagged colonies are present and accounted for after 2 1/2 years! Having all of the colonies survive is actually fairly miraculous based on what we have seen in other locations. But the population here in Navassa has done more than survive, all of the colonies are still healthy and growing! The picture on the right shows the same colony after 2 1/2 years and if you compare them carefully, you can tell that the branches are longer and the base is wider as the colony has grown. We did not find any new colonies as I had hoped and that is somewhat surprising since this population seems to have high recruitment, but where Elkhorn corals are concerned, not dying is alone cause for celebration! We are planning to try (weather permitting) to visit our study plots on the north coast tomorrow and hope that we will be pleasantly surprised there as well! --Dana

White-Tail Tropicbird joins the list

The commanding officer of the Nancy Foster Ralph Rogers is an experienced birder and has also been on the lookout for us. Our Ship was near the South side of the island when he saw the unmistakable long white tail of the tropic bird. I quickly joined him on the bridge level borrowed his binoculars and got a nice look for myself. Later in the week we are planning to do some operations near the South end so I’m hopeful my Dinghy will get a close encounter with one of Navassa’s tropicbirds.
Mike - photo wikipedia

Fishery data collection

Unfortunately, we have not yet received any visits from Haitian fishermen at the island. However, it seems that fishers were here very recently, as we have come across a number of fish traps in transit to dive sites. We expect the fishers might come back in the near future to recover the traps they had deployed. In the absence of other fishery data collection, today we began taking CPUE (catch per unit effort) data for the traps by recording the species and size of fish inside each trap. We visited three traps this morning and were quite surprised to see the number and variety of fish that had been caught, including surgeonfishes, small groupers (grasbys and coneys), trunkfishes, and filefishes. Also surprising was the sheer size of the traps; these are transported on the fishers’ small boats all the way from mainland. The traps are weighted with rocks and are marked with a line attached to floating water bottles.

Tomorrow we will continue with the CPUE data collection for the other four traps that have been observed around the island. And of course, we are eagerly awaiting the arrival of Haitian fishermen!

- Mandy

RVC Methodology

Reef fish visual census (RVC) data are collected using a stationary point sampling technique which utilizes standard visual sampling methods. This year we will try to complete censuses at 75 stratified random sites from the north and west side of the island (red dots on map). At each point two divers record all fish species observed in five minutes within an imaginary cylinder extending from the surface to the bottom within a radius of 7.5 meters (24.6 feet) from the observer. After recording species for five minutes, divers next record quantitative data for these species; estimated number of individuals and the minimum, maximum, and mean estimated length. New species to the sample, which include the rare or cryptic species, observed after the initial 5 minutes are also recorded, along with estimates of length for selected species, to expand the species list composition. An underwater digital camera is used to record unknown species, as well as document fish assemblages.
Dave McClellan


Each morning at 0730-0745 scientists, dive teams and coxswains (the person in charge of a boat- the literal translation meaning ‘boat servant’; cox- a small boat aboard a larger boat and swain- someone in authority); assemble on the back deck for a morning briefing. During this meeting, objectives for the day’s mission are discussed by the chief scientist Dr.Margaret Miller, and a pre-dive safety check is conducted by the unit diving supervisor Dave McClellan. Each diver/scientist is responsible for making sure their diving and sampling gear gets loaded on their respective boats before they are launched. Once the small boat is launched it is very difficult to come back and retrieve anything left behind. We have coral teams, fish teams, and mixed teams, so getting the correct gear on the correct boat is very important and is predetermined the night before at our science meeting. The small boats are then lifted over the rail by the crew of the Nancy Foster and put into the water. The science divers then go down a ladder and onto the boats. This is a picture of our principal investigator (PI) Margaret Miller taking that last big step.


Tuesday, April 28, 2009

Hunting Staghorn...

Staghorn coral that is! Like its close relative elkhorn coral, staghorn coral was listed as a threatened species under the US Endangered Species Act in 2006.
When I first visited Navassa in 2002, we encountered a few very small thickets of staghorn coral and scattered colonies on several of our dives to the deeper patch reefs. When we returned in 2004 we found coral disease actively spreading around the reefs of Navassa and only saw 1 colony in our many dives. In 2006 we found substantial coral bleaching and only found 2 small sprigs of this coral, one of which was diseased and dying! So this year we have once again issued an ALL POINTS BULLETIN for staghon coral sightings amongst the 12 divers in our group! So far one small colony has been seen by Jack Javech of the fish counting team. If the weather continues to be too rough to survey elkhorn coral along the wall I will join the hunt for this now rare and emperiled coral. Although it appeared to be doomed on our last visit, this is a relatively fast growing coral and I am hoping that we will find small colonies that have persisted through these tough times! --Dana

Boobies & Frigatebirds up close

The operations are finally under way and we are all happy to be diving!!!! The boobies & Frigatebirds appear to be interested in our presence but lose interest just as fast when they learn we have no hand-outs for them. They are swooping down much closer to our little boats then they do to the Nancy Foster perhaps because our small boats resemble Haitian fishing craft. We are all excited because we are getting great views of these spectacular birds as they circle above us. Dana Williams and Abel Valdivia were working very close to shore when Abel managed to snap the picture of the day just before a research dive.

Photo Abel Valdivia

Fish count update

Twelve RVC sites have been sampled on Monday and Tuesday with 24 fish count samples in total. A small colony of staghorn coral (Acropora cervicornis), pretty rare down here, was noticed during a habitat assessment and reported to Margaret. Most fishes seen have been small, as expected. The most common grouper seen are small species, the graysby and coney. A school of twelve 25 cm to 30 cm schoolmaster snapper was seen today. During that same dive three species of triggerfish were observed: queen triggerfish, ocean triggerfish and black durgon. Grunts are extremely rare here, but three French grunt have been observed. A few small barracuda have been seen, as well as some jacks. Fairy basslets (photo above), squirrelfishes, and planktivores such as the blue chromis and creole wrasse, are the most common fishes so far.

Dave Mc, Jack, Natalia (photo), Joe, Mike and Dave G.

Its always the weather

Tuesday morning finds us with 5-6 ft swells, similar to yesterday, but with a significant wind kicked up. We all gathered on deck this morning after a noisy and bumpy night. It seemed clear that small boat (and hence, diving) ops were not a safe option for now. The conditions yesterday were marginal for getting in and out of the small boats since we have to climb up/down a 'Jacobs ladder' while the small boat is bouncing beside the ship. We had a few bumps and buises yesterday so for now we are standing by. It also seems unlikely that the Haitian fishermen will be venturing accross in these conditions.

To a large extent the success of one's efforts, no matter how carefully planned and prepared, is beyond one's control, at the whim of the weather. This is a major aspect of being a field scientist that is very much like farming. On a long, remote trip such as this one, the risk is even greater that the productive work can get completely blown out. Nearer to home, we are usually huddled around a weather radio, wondering if/when conditions might improve. In a remote place such as Navassa, the resolution of the weather forecasts is not very informative, so we are mostly just waiting and hoping for calmer conditions.
Photo Abel Valdivia

Navassa’s Boobies

On Sunday afternoon we arrived at Navassa Island. Well, we are not actually going onto the island, our ship will be anchoring about ¼ mile out. We will be doing our diving operations from small dinghies launched and retrieved directly from the Nancy Foster. Our Boobie count has gone from a handful to the hundreds. We are seeing Brown Boobies in multiple year classes and color morphs and we are also sighting both juvenile and adult Red-Footed Boobies as well. Most of our Boobie sightings are coming in the late afternoon as the birds return to the island.

Monday, April 27, 2009

Research on Navassa Artisanal Fishers

Having previously visited Navassa six times with both NOAA and FWS I am here this time (yes, again!) to work with the scientific team in general, but, specifically with the Haitian fishers.
Due to extremely poor economic conditions combined with unregulated and unsustainable exploitation of marine resources back in Haiti which have caused the overexploitation of resources, the fishers often find it worth the hazardous crossing (35+ miles!). Under sail in their tiny 12’-15’ handmade wooden boats, usually without a motor, the crossing, which can take two or more days is extremely dangerous and there have been several occasions when boats have not made it home, with the loss of the 4-6 man crew.
My primary role on the cruises/expeditions it to talk to the fishers present at Navassa and to determine what type of activities they are engaging in including: where the fishers are coming from, what types of gear they are using, what they are catching, how long they stay, how many come, etc. Over the many trips to Navassa, as well as work FoProBiM has undertaken back at the home fishing villages of the Navassa fishers, we have developed quite a bit of trust with these fishers and they have generally been willing to cooperate in this research.
Along with the above activities undertaken at Navassa back in Haiti FoProBiM is undertaking resource use conflict resolution, association building, and environmental education classes, as well as trying to determine what can be done to develop sustainable fisheries and/or alternative income generating activities so the fishers will no longer need to take the dangerous voyage to Navassa. --Jean Wiener

Baltimore Oriole joins the bird list

We are happy to report an unexpected addition to the bird list. On Sunday Mandy Karnauskas noticed a little orange and black bird circling our ship. Patricia Morrison quickly ran down to retrieve her binoculars and identified our little bird as a male Baltimore Oriole. The bird made a few circles around our ship then departed to the North. We are not sure if this was a local bird comming from a nearby island of one making his spring migration to North America from it's wintering grounds in South or Central America. We would like to think our bird is a long distant travler also we added the Red-Footed Boobie to our list.

Sunday, April 26, 2009

Working hard or hardly working?

This is my first visit to Navassa, and I am quite excited to see the island. We are about 5 hours out and we can already see the Haitian coastline from the ship. This is also my first research cruise. I was invited to participate because I speak Haitian Creole, I can count fish, and I am a certified Nitrox diver. I imagine that this is a rare skill set that will only come in handy a few times in my life. I am very grateful to have been invited to participate on such an exciting cruise.

Before we arrive at Navassa, I need to finish rewriting my qualifying exams! I have attached the photo here so that my advisor can see how hard I am working.
-- Mandy Karnauskas

Walls of coral

The underwater sides of the island are nearly vertical from the surface down to about 80 feet (25m) and the water is incredibly clear making for some spectacular vistas! It is hard to tell from a photograph, but the lower part of this frame is at about 30ft deep. Where I do most of my diving in the Florida Keys the visibility is probably half of what you see in this picture taken in Navassa in 2006. Aside from making for awesome scenery, it also means that sunlight reaches deeper than at home. Elkhorn coral generally does not have enough light to grow below 30ft in Florida however we have found small colonies living at nearly 70 feet in Navassa!

Since most of the shallow area is wall, all of the corals that usually live on the shallow part of a typical reef have to find a way to live and grow sideways! In past years we have found Elkhorn coral growing and thriving in this environment. However, rather than growing up like a tree as it usually does, it encrusts the walls of Navassa forming a carpet of Elkhorn with stubby branches!

In 2006 I snorkeled around two thirds of the island (about 10hrs in the water!) and marked each colony with a GPS point so that we could record where they were located and how many there were. The blue line on the map is where I snorkeled and each orange dot is a colony of Elkhorn coral! I counted approximately 1800 colonies in the nearly 7km of coast I was able to snorkel. It is extremely hard to count them because they grow very close together but the GPS makes it a little easier!
This year we hope to repeat this survey but it will depend on the weather conditions while we are there. To do this survey I have to swim very close to the rocks and big waves can make it a little dicey to say the least! --Dana

Saturday, April 25, 2009

Pelagic birds

I am pleased that Patricia Morrison of the USFWS has eagerly joined the birding team. The path the Nancy Foster is taking to get to Navassa after departing the San Juan harbor is a West heading along the north shore of Puerto Rico. We then head south through the Monna passage and turn West along the southern coast of Dominican Republic and Haiti until we reach the windward passage (yes over two days steam). Navassa Island sits in the Windward Passage to the west of Haiti. We have been out of sight of land for most of the transit but together we have teamed up to see some nice pelagic birds and a long decision about including the numerous flying fishes scattering before the ship in our bird list. At this point our Pelagic bird list includes Royal Tern, Brown Noddy Tern, Brown Booby, and a graceful Magnificent Frigatebird. We are hopeful that tomorrow will bring us a white tailed tropic bird.

Bird Observations from Puerto Rico

The first day we arrived in San Juan myself and about eight others had a chance to take a walk around town and do some sightseeing and opportunistic birding. I started out hopeful that I would see a scaly-napped pigeon or a smooth-billed ani mixed in with the centuries old buildings and green spaces of old town but came up empty handed. I noticed a lot feral cats which could help to explain the lack of species and numbers of individuals that I saw. Although my targets were never sighted I did see just under a dozen species including common pigeon, white wing dove, grey kingbird, gold eyed grackle, brown booby, gull sp., pine warbler, house sparrow, zebra finch, Caribbean parrot, and my personal favorite the bananaquit.
Mike Judge

Reef fish surveys

Over three hundred species of fish have been identified from Navassa waters, new species documented for the area from every cruise. Five fish counters (Jack Javech, Dave Gothan, Mike Judge, Joe Contillo, and Natalia Zurcher) will sample 75 sites, two to four samples per site, over eight days at Navassa. We are using the data to assess population changes and ecosystem responses to fishing by artisinal fishermen from Haiti. Declines in reef fish biomass seems to be occurring with less larger fishes seen every year. A range extension of the reef cave brotula Grammonus claudei, photographed by Keith Pamper (Shedd Aquariun) during the November 2006 expedition, was quite exciting. Also seen during 2006 was a 5 foot goliath grouper Epinephelus itajara, unexpected since there is no habitat around the island for juveniles. We are hoping to photo-document as many species as possible during our fish counts, and since our sampling method is non-destructive, we take pictures and leave the fish alive.

Dave McClellan


This is my fifth visit to Navassa. I came for the first time in 2000 and was amazed at the clear water, large fish, and healthy corals. My susequent visits, at approximately 2 year intervals, have all held (mostly unpleasant) surprises. Because Navassa is so remote and our observations are so intermittent, a lot can happen that we are not able to observe directly. However, in 2004, we encountered a coral disease outbreak and greatly expanded fishing effort while in 2006, a coral mass-bleaching event was underway. On the good side, the threatened elkhorn coral (Acropora palmata) population at Navassa was surprisingly robust and healthy in 2006 and the water was still spectacularly clear. I am nervous what surprises await us this trip. Hopefully at least some are good ones.

Margaret Miller