Crevalle Jack

Caranx hippos

Crevalle Jack
Photo credit: Robert Aguilar, Smithsonian Environmental Research Center on Flickr

Status

Endangered

Physical 

The crevalle jack comes in a range of colors, from a blue-green to green-gold back, a silver or yellowish belly, and yellow fins. Juveniles will have several dark vertical stripes along the body. They have a black spot on gill cover and on the base of the pectoral (side) fin, which distinguishes them from other jack species. They also have bony scutes along the lateral line, near the base of the tail. Adults grow to 24 in (70 cm) on average. They often make a croaking noise when caught by fishermen.

Image by Robert Aguilar, Smithsonian Environmental Research Center on Flickr

Habitat

Range from Nova Scotia to the northern Gulf of Mexico and further south to Uruguay. Also found in the western Mediterranean and parts of Africa. In the US, they’re more common to the south and especially the Gulf of Mexico, so most crevalle jack in the Barnegat Bay are juvenile southern strays that have made their way north. They live from the coastline out to the continental shelf, including upstream currents, reefs, and offshore areas.

 

Feeding 

Crevalle jacks are predatory fish that hunt in schools. Adults eat fishes, shrimp, and other marine invertebrates. Juveniles feed on smaller fish and crustaceans.

 

UNKNOWN

There is limited data available to quantify Wetland and Riparian Buffer Preservation, or updated data to quantify Wetland Acreage. The BBP has obtained funding and will begin assessment efforts for both targets, in the next few years.

 

 Hard Clam abundance has not been updated since 2012. Recovery of the stock will be guided by the Fishery Management Plan for Hard Clams, which is under development with the NJDEP, BBP, and other organizations. Reclam the Bay and other partners have continued to plant clams for restoration purposes. Continued plantings in strategic locations which maximize survival and reproduction is one strategy to pursue in the coming years. This work can use a model developed by Rutgers with BBP funding which identified areas where planted clams could have the greatest dispersal of their larvae and thus potentially maximally contribute to the recovery of the stock.

 Water Withdrawals were over the target in the 2021 report; USGS has not yet completed its latest update, so a definitive determination of status is not available. However, additional NJDEP data show that it is likely that we continue to not meet the target. Per capita water use has gone down, demonstrating the effectiveness of water-saving appliances and practices, but that decrease has been offset by population gains. 


IN PROGRESS

New maps quantifying Submerged Aquatic Vegetation extent were developed, but poor image clarity resulted in a high degree of uncertainty in the total acreage. NJDEP and Rutgers are working to resolve the uncertainty of these maps, and improve the total acreage estimate. Funding has also been obtained for further research and restoration activities. Several groups are developing potential restoration actions.

The USGS has completed the first phase of its study to identify minimum ecological flows in select Barnegat Bay tributaries. USGS scientists compared streamflow statistics between historical and current time periods to better understand trends in watershed flow conditions. This work provides a foundation for developing ecological flow targets in the Barnegat Bay watershed.  Similar to SAV extent, funding (approximately $450K) has been obtained by the BBP to complete the remaining phases necessary for threshold determination.

 

TARGETS ACHIEVED

No targets can be considered “Achieved” at this time.

 

NOT ACHIEVING

Several Public Swimming Beaches exceeded their safe swimming standards more frequently than during their baseline time period (2016-2018).

While most beaches are routinely safe for swimming, several problematic areas such as Beachwood, Hancock, Windward, and several lake beaches need track-down studies and restoration to pinpoint and address sources of bacteria.

Acres of Approved Shellfish Waters decreased from the last report. While this decrease was small, it represents a loss of previously approved waters. Similar to public beaches, track-down studies and restoration work are needed to pinpoint and address sources of bacteria.

 

Crevalle Jack
Photo credit: Robert Aguilar, Smithsonian Environmental Research Center on Flickr